Keywords: Nanomaterials, Modeling & Simulation, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: This study introduces a comprehensive multiscale modeling framework for simulating field-effect transistor (FET) circuits based on two-dimensional (2D) materials. The approach integrates a suite of open-source tools to model electronic behavior across scales—from the atomic level to the device and circuit levels—ensuring accurate and scalable simulations. Structural visualization and modification are performed using VESTA, followed by electronic property calculations using Quantum ESPRESSO. Maximally localized Wannier functions (MLWFs) are then extracted using Wannier90 to construct accurate Hamiltonians. Device-level simulations are carried out with NanoTCAD ViDES to assess transistor performance. To bridge the gap from material to circuit design, Cadence Virtuoso is incorporated, enabling advanced simulation and optimization of circuit-level behavior using Verilog-A. The reliability and robustness of the proposed multiscale framework are confirmed through benchmarking against existing experimental and simulation data, demonstrating strong agreement and high predictive accuracy. By leveraging open-source tools, this methodology remains cost-effective and accessible to the broader research community. Overall, the framework not only accelerates the design and optimization of 2D material-based FETs but also lays the groundwork for their integration into digital VLSI circuits, paving the way for next-generation high speed, low-power logic and memory applications.

Keywords: Nanodiamond and nanocarbon structures: materials and devices, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: Interdigitated capacitor (IDC)-based sensors are widely adopted in wearable and flexible electronic devices due to their high sensitivity and compact design for microfabrication. The capacitive-based sensors can be easily fabricated using laser-induced graphene (LIG), a low-cost, mask-free, and scalable technique. This study explores the influence of various geometry parameters, specifically the spacing between IDC fingers, on the performance of planar LIG-based IDCs. The 3D model of the LIG-based IDC was simulated using COMSOL Multiphysics and compared with the IDC fabricated by ablating a polyimide (PI) film using a CO2 laser engraving machine. The COMSOL simulation results revealed that reducing the gap between IDC fingers enhances the electric field intensity and fortifies the coupling between the two electrodes, resulting in higher capacitance. LIG-based IDCs with a space between the fingers varying from 0.3 mm to 0.7 mm were fabricated, and the finger spacing of 0.3 mm exhibited higher capacitance, closely matching the simulation results.

Keywords: Nanometrology & Characterization, Modeling & Simulation, Education in nanotechnology
Abstract: This paper provides an overview of the evolution and significance of System on Chip (SoC) verification within semiconductor design. As SoCs incorporate increasingly complex and heterogeneous components, traditional verification methods are proving insufficient to address the challenges of functionality, integration, and interoperability. Advanced verification strategies—such as coverage-driven verification, assertion-based verification, formal verification, emulation, and the widespread adoption of the Universal Verification Methodology (UVM)—have greatly enhanced the scalability and efficiency of the verification process. This review examines various SoC verification techniques, evaluating their strengths and limitations, and explores emerging trends focused on accelerating and improving the reliability of verification for next-generation SoC designs.

Keywords: Nano-acoustic Devices, Processes & Materials, Nanomaterials, Nano-biomedicine
Abstract: High interstitial pressure and solid stress in tumors pose significant barriers to effective intratumoral drug delivery. To address this, a 320 kHz ultrasound transducer was integrated into a trocar, featuring dual side-facing acoustic apertures and an injection lumen for delivery of therapeutic agents. After trocar integration, characterization revealed a peak-negative pressure output of up to 2.8 MPa at 100 V. Dye perfusion experiments using agar phantoms demonstrated that ultrasound exposure substantially increased dye penetration, with Group 1 (240 cycles, 10% duty cycle) achieving the largest perfused area of 124.2 mm². These results support the potential of ultrasound devices to enhance localized particle transport in tumor-mimicking environments.

Keywords: Nanomagnetics, Nanoelectronics: Emerging material and device challenges in futuristic systems, Nanomaterials
Abstract: Nanocrystalline zinc ferrite (ZF) is synthesized by using a Teflon-lined stainless-steel autoclave via a low temperature solvothermal route. The synthesized ZF nanoparticles were characterized for phase purity and morphology using X-ray diffraction (XRD) and scanning electron microscopy (SEM). A toroid-core (ZF1) was fabricated by pressing the ZF nanoparticles into a toroid using a binder and coated with epoxy for enhanced mechanical robustness. To assess the influence of resin and binder removal, a similar toroid (ZF2) was sintered at 700 °C and subsequently subjected to characterization. Inductors formed with the cores so fabricated were evaluated through frequency-dependent measurements of permeability and inductance up to the MHz range. The results indicated that the inductance and Q factor were stable up to 80 MHz, while permeability was constant up to 550 MHz. Both the ZF1 and ZF2 inductors demonstrated identical behaviour in terms of inductance measurements. To evaluate on-load performance, the inductor (ZF1) was tested in a GaN-based Synchronous Buck Converter (SBC) operating from 24 V to 12 V at a power rating of 15 W. The switching frequency of the converter was varied from 500 kHz to 1 MHz. Experimental results revealed that ZF inductor exhibits lower losses than those with conventional ferrite core. Furthermore, under high flux linkage conditions typically associated with higher loss and temperature rise, the ZF cores show excellent thermal stability, highlighting its applicability for high-frequency power electronics.

Keywords: Nanofabrication, Nanomaterials, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: Noble metals and metal oxide semiconductors have been utilized for gas sensing applications with machine learning approaches and various hardware topologies. This paper presents a novel single-chip room temperature E-Nose integrating multiple gas sensing technologies to address cross-sensitivity, instability, and high-power consumption challenges. We deploy an array structure based on crystalline Si tandem FETs functionalized with metal oxide semiconductors (VO2, TiO2) and noble metals (Au, Pd) for enhanced sensitivity and selectivity. The fabricated E-Nose is electrically characterized and tested using a PDMS-based microfluidic channel in the presence of NH3, NO2, H2S and Air. The response of each FET to the gases varies due to the versatile sensing layers. This capability is further leveraged by developing a machine learning classifier based on Linear Discriminant Analysis. The trained model achieves 89.66% overall accuracy in gas classification without data pre-processing. This room-temperature, low-power, standalone, intelligent, multi-gas E-Nose showcases enhanced sensitivity and selectivity due to its unique hybrid nanomaterials, promising significant gas-sensing technology advancements.

Keywords: Nano-fluidics and integrated bio-chips, Nanofabrication, Nano-biomedicine
Abstract: Accurate pH monitoring is essential in cell culture systems to maintain cellular health and function. Traditional glass electrode sensors provide high accuracy but are unsuitable for compact platforms, while miniaturized alternatives often face limitations in sensitivity, stability, or integration complexity. To address these challenges, we developed a compact cell culture monitoring system that combines multispectral imaging with a CMOS image sensor. The system integrates a custom six-band multispectral filter array with a PDMS microfluidic channel on a CMOS image sensor. Multispectral images are processed using a convolutional neural network to accurately predict pH, while a deep learning-based segmentation model is employed for cell counting. The results demonstrate the potential of this system as a lab-on -chip platform for cell culture monitoring.

Keywords: Nanofabrication, Nanosensors & Nanoactuatuators, Nanomaterials
Abstract: The global rise in cannabis abuse poses a significant The global rise in cannabis abuse poses a significant threat to public health and safety, emphasizing the necessity for sensitive and portable detection technologies. We developed a biosensor device that integrates silicon nanowires (SiNWs) for the selective detection of tetrahydrocannabinol (THC). UV photolithography and e-beam thermal evaporation were used in the fabrication of SiNW-integrated biosensor devices. The devices were functionalized with (3-aminopropyl) triethoxysilane (APTES) through covalent bonding (Si-O-Si) and prepared for antibody conjugation. The recombinant tetrahydrocannabinol antibody (anti-THC) was covalently conjugated to the APTES-functionalized SiNW. Sensing studies were conducted in the presence of THC derived from cannabis. The device and surface characteristics were determined using various analytical techniques, including X-ray photoelectron spectroscopy, confocal Raman spectroscopy, Fourier-transform infrared spectroscopy, UV-vis spectroscopy, and field-emission scanning electron microscopy (FE-SEM). The average SiNW measures 1.08 µm in length and 50 nm in thickness. Its electrical and sensing characteristics were assessed through IV and spectroscopic studies, revealing a lower detection limit of 1 × 10-7 M.

Keywords: Nanofabrication, Nanosensors & Nanoactuatuators, Nanomaterials
Abstract: This work investigates a silicon nanowire (SiNW) based nano sensor device to detect the hazardous para-nitrophenol (P-NP) molecule. Due to their outstanding electrical conductivity and high surface-to-volume ratio, metal-deposited SiNW-based nanosensor devices have attracted considerable attention. Rather than the more popular gold, silver metal was deposited in this case using the E-beam metal deposition technique. The device demonstrated superior label-free detection ability with an instant response time to the target molecule, resulting in a low limit of detection (LOD). To confirm the successful surface modification using TESBA, various spectroscopic techniques were employed.

Keywords: MEMS/NEMS, Nanofabrication, Nanopackaging
Abstract: The thermal management is a critical challenge for high-density heterogeneous integrated systems in the post-Moore era. In this paper, we present a microfluidic cooling strategy enabled by silicon-based microchannels with sinusoidal pin-fins. The microchannels are etched in a silicon wafer by deep reactive ion etching (DRIE), leaving arrayed pin-fins in a sinusoidal profile. A BF33 glass wafer is then bonded onto the microchannels by benzocyclobutene (BCB), serving as the cover plate. According to the measurement results, the cooling efficiency of the fabricated microchannels enhances with the microfluidic flow rate, with a maximum temperature reduction approaching 300 °C for a heat source heated by 12.34 W DC power under a microfluidic flow rate of 144 mL/min. Note that the measurement results agree well with the finite element analysis (FEA) simulations with a deviation below 5%, proving the stability of the fabrication scheme as well as the feasibility of the proposed microfluidic cooling strategy in improving the thermal management of 2.5D heterogeneous integration.

Keywords: Nanopackaging, Nanomaterials, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: This paper investigates the potential of using thin coatings made from industrial-grade graphene as electromagnetic shields in applications where replacing conventional metallic shields could result in significant payload reduction. The nanomaterial used in this study is a specialized nanocomposite with a very high concentration of graphene nanoplatelets, produced through an industrial fabrication process starting from expandable graphite. The case study presented here demonstrates the effectiveness of an electronic enclosure made of a polymeric material coated with the proposed nanomaterial in significantly reducing—or even completely eliminating—electromagnetic emissions from antennas operating in the 1–6 GHz range.

Keywords: Nanorobotics & Nanomanufacturing, Modeling & Simulation, Quantum, Neuromorphic & Unconventional Computing
Abstract: The global semiconductor industry demands continuous innovation to improve equipment output and maintain competitiveness. This paper explores the integration of digital technologies such as Artificial Intelligence (AI), Machine Learning (ML), data mining, and predictive maintenance into semiconductor manufacturing. By examining a range of case studies and methodologies, we highlight technology management strategies that enhance operational efficiency, reduce downtime, and boost Overall Equipment Effectiveness (OEE). Our findings show that a systematic adoption of data-driven decision-making and intelligent digital infrastructures can lead to measurable improvements in tool performance and throughput.

Keywords: Modeling & Simulation, Nanofabrication, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: This paper discusses the development of optimized multi-dimensional design spaces for three-dimensional nano-sheet field-effect transistor for both p-channel and n-channel metal-oxide semiconductors. These designs of experiments were simulated using Synopsys’ Technology Computer Aided Design (TCAD). Strategic optimization of the meshing scheme allowed for a 71% reduction in the device simulation runtime without sacrificing the model accuracy. Simulation studies evaluated the impact of different combinations of the gate, spacer, and contact lengths on electrical characteristics, including the total capacitance as well as effective and off currents. The optimal combination with gate, spacer, and contact lengths of 14 nm, 4 nm, and 20 nm respectively resulted in the successful minimization of the figure of merit, which is the ratio of total capacitance to effective current. Diminishing returns were observed after three nanosheets. Reducing the nanosheet thickness from 5 nm to 3 nm also improved this performance metric by 2.1%, 2.1%, and 2.8% for low, standard, and high voltage threshold devices respectively. Effective and off currents were closely matched for NMOS and PMOS devices with multi-nanosheets. The optimized design space for PMOS had a 62% increased nanosheet width and 11% increased metal gate work functions across devices with different threshold voltage conditions compared to its NMOS counterpart. PMOS capacitance trended above NMOS and had slightly worse figure of merit. A performance analysis using the optimized NMOS and PMOS devices was carried out on a 31-stage ring oscillator with a fanout of 4. The methodologies performed through these simulation studies can serve as tools for performance prediction, bottleneck identification, and optimization of future transistor designs of novel device technologies in semiconductor foundries.

Keywords: Modeling & Simulation, Nanosensors & Nanoactuatuators, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: Abstract—We present a finite element modeling study to optimize nanopore geometry in microelectrode arrays to enhance sensitivity in electrochemical sensing. Each 10 µm-diameter electrode comprises a Cr/Au thin film on a fused silica substrate, conformally coated with an 〖SiO〗_2 layer that introduces surface defects acting as nanopores. The array consists of seven electrodes arranged in a hexagonal close-packed (HCP) configuration. To minimize crosstalk between adjacent electrodes, the spacing was optimized to ensure a 90% reduction in electric field strength at the nearest neighbor, resulting in inter-electrode distances greater than 9 µm. The electrochemically active area is defined by separate, 0.6 µm-deep epoxy resin wells (each containing a single nanopore with different pore radius) patterned on top of the 〖SiO〗_2 layer. The epoxy resin wells were filled with 20 mM Potassium Ferrocyanide (K_4 [Fe 〖(CN)〗_6]) and 0.5 M Potassium Chloride (KCl) as the supporting electrolyte. Redox reactions occur at the exposed Au surface at the base of each nanopore. To optimize pore geometry, we swept the 〖SiO〗_2 thickness which definiens the pore height (depth) from 5 nm to 20 nm in 150 steps, measuring the resulting diffusion-limited current. This analysis was conducted across five different pore radii—10, 20, 50, 80, and 100 nm— in separate epoxy resin wells, to construct a comprehensive performance map. The highest diffusion-limited current, ~3 nA, was observed at a pore radius of 80 nm and height of 11.8 nm, corresponding to an optimal r/h ratio of 6.77. Notably, only the 10 nm pore exhibited non-classical transport behavior caused by electric double layer overlap. These findings provide practical design guidelines for development of high-resolution, multi-electrode single-entity electrochemical detection platforms. Key words: Finite Element Modeling, Nanoporous Electrochemical Sensors, Diffusion-Limited Current.

Keywords: Modeling & Simulation, Fundamentals and applications of nanotubes, nanowires, quantum dots and other low dimensional materials, Quantum, Neuromorphic & Unconventional Computing
Abstract: The deviations from the integer quantization of conductance in units of 2e²/h in the two-terminal measurement of one-dimensional (1D) ballistic channels defined electrostatically on the two-dimensional electron gas (2DEG) have generally been attributed to correlation and impurity-driven effects. We show the role of random disorder potential and its distribution on the quantized conductance using the tight binding model. Our results show similarities to anomalies observed in experiments, such as the “0.7 conductance anomaly”, which is one of the unsettled conductance features in the physics of 1D quantum wires.

Keywords: Modeling & Simulation, Nano-optics, Nano-photonics & Nano-optoelectronics, Nanomaterials
Abstract: We present a simulation-guided design for a multilayer surface plasmon resonance (SPR)-based biosensor that can detect changes in the refractive index of a target induced by analytes. Surface plasmons are excited through a hybrid Kretschmann configuration with a low-refractive-index calcium fluoride (CaF2) prism under transverse magnetic polarization illumination. In the sensing architecture, the copper (Cu) layer is a plasmonic metal, overlaid with a thin nickel (Ni) layer that protects it from oxidation. To improve analyte coupling and electromagnetic confinement, a dielectric layer of barium titanium oxide (BaTiO₃) and a monolayer of graphene oxide (GO) are used. The layer structure is iteratively optimized employing the transfer matrix method for angular interrogation at a wavelength of 1064 nm, focusing on key performance metrics including sensitivity, minimum reflectivity, and figure of merit (FOM). The finite element method-based simulation confirms SP excitation through consistent and optimal performance of individual layer thicknesses with Cu thickness of 30 nm and BaTiO₃ thickness of 5 nm. The SPR-based sensor (CaF2-Cu-Ni-BTO-GO) is designed and has achieved a sensitivity of 157.8°/RIU and an FOM of 17.48 RIU-1 while detecting the presence of the E. Coli bacterium in the water, indicative of the biosensor's application.

Keywords: Modeling & Simulation, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: Nanosheet-based CMOS technology is a key structural advancement for semiconductor nodes at 3 nm and beyond. A critical process step involves the sequential stacking of SiGe and Si nanosheets (NSs) on a Si substrate, which induces global stress due to lattice mismatch. This leads to residual tensile stress in the Si NS channels of gate-all-around (GAA) transistors after partial relaxation of the SiGe layers during different process steps. The residual stress is influenced by fin geometry and material parameters. Finite element simulations show that in-plane stress along the channel direction (σxx) increases from 0.19 GPa to 0.56 GPa, and transverse stress (σyy) from 0.392 GPa to 1.25 GPa, as Ge mole fraction in SiGe increases from 0.15 to 0.45. This strain alters device performance: drain current decreases by ~5% in n-type NS-GAA transistors and increases by ~6.4% in p-type devices. These findings are critical for guiding strain engineering strategies to optimize performance and reliability in nanosheet-based CMOS and related heterostructure devices.

Keywords: Modeling & Simulation, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: Complementary Field-Effect Transistors (CFETs) are among the most promising candidates for next-generation technology nodes due to their potential for aggressive footprint scaling, improved density, and reduced parasitics through vertical integration. While significant progress has been made in CFET design and performance, their long-term reliability—particularly under negative bias temperature instability (NBTI)—remains largely unexplored. In this study, we present a detailed NBTI reliability analysis of p-type CFETs using calibrated Sentaurus TCAD simulations. The investigation focuses on the impact of multi-bridged-channel configurations, ranging from single-channel (1-Ch) to triple-channel (3-Ch) devices, under varying gate stress voltages and time durations. Results show that increasing the number of channels significantly reduces degradation in drain current (mathrm{I_{DS}}) and threshold voltage shift (Deltamathrm{V_{th}}), even under identical trap concentrations and stress conditions. Temperature-dependent simulations (300–420 K) further confirm that while NBTI accelerates with T, the relative benefit of multi-bridged architectures remains robust. A physics-based hydrogen transport model—tracking the diffusion of hydrogen-species—reveals that while total hydrogen availability increases with channel count, the impact on degradation becomes diluted due to current sharing and distributed interface stress. These findings highlight the NBTI resilience of multi-bridged p-CFETs and reinforce the value of architecture-aware modeling in advanced technology nodes.

Keywords: Modeling & Simulation, Quantum, Neuromorphic & Unconventional Computing, Education in nanotechnology
Abstract: The extraction and modeling of device parameters for resistive random-access memory (RRAM) circuits are hindered by significant device variability and high-dimensional parameter spaces. Traditional SPICE workflows depend on manual file manipulation, limiting both scalability and reproducibility. We introduce SpiceXpanse, an open-source framework that automates RRAM model calibration through configurable parameter exploration, parallel HSPICE execution, and interactive visualization. The modular optimization engine accommodates arbitrary sampling schemes, user-defined heuristics, and composite loss functions, yielding physically consistent fits while maintaining full procedural transparency. In preliminary tests on ten experimentally fabricated passive RRAM cells, the framework completed the entire extraction workflow without manual edits and leveraged parallel HSPICE runs to accelerate evaluation of candidate parameter sets. As a case study, we applied a shadow memory module-a series-resistance compensation technique that adds calibrated resistance values to homogenize device behavior to align RESET thresholds at 2 V and significantly reduce threshold dispersion. SpiceXpanse thus offers a scalable, reproducible methodology that improves modeling accuracy and efficiency, with particular utility in neuromorphic and in-memory computing.

Keywords: Fundamentals and applications of nanotubes, nanowires, quantum dots and other low dimensional materials, Nanomaterials, Nanofabrication and Nanomanufacturing for Low-Dimensional Nanomaterials and Nanodevices
Abstract: Photothermoelectric (PTE) detectors have emerged as a promising technology for broadband infrared (IR) detection due to their unique ability to convert thermal radiation into electrical signals without requiring an external bias voltage, enabling operation under ambient conditions. However, conventional PTE detectors often suffer from complex fabrication processes, poor material stability, limited flexibility, and inconsistent film formation, hindering their practical applications. To address these challenges, we present a novel flexible IR PTE detector based on a multi-walled carbon nanotube (MWCNT)/poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) nanocomposites, fabricated using a laser ablation patterning technique. The device is realized through a low-cost two-step process: (1) preparation of a stable MWCNT/PEDOT:PSS dispersion into film and (2) direct laser patterning to form well-defined, homogeneous nanocomposite structures. By optimizing the laser ablation parameters, we fabricated the detector exhibits outstanding mechanical flexibility, maintaining stable performance under 100 bending cycles. With its excellent broadband IR detection, flexibility, this MWCNT/PEDOT:PSS-based PTE detector opens new possibilities for wearable health monitoring and smart Internet-of-things (IoTs) systems.

Keywords: Fundamentals and applications of nanotubes, nanowires, quantum dots and other low dimensional materials, Nanosensors & Nanoactuatuators, Nanomaterials
Abstract: The inherent ability of graphene to effectively adsorb hydrogen sulfide (H₂S) makes it a promising material for use in selective and sensitive gas sensors. Using Density Functional Theory (DFT), this study explores how hydrogen sulfide gas molecules adsorb on graphene nanosheets in their undoped form, with zinc decoration, and when doped with zinc and copper. The structural modifications of graphene following gas molecule adsorption on pristine, metal-doped, and metal-decorated graphene nanosheets have been examined and analyzed. Transport simulations demonstrate that graphene nanosensors doped with Zn exhibit direction-dependent electronic responses when tested for the armchair and zigzag orientations. The study highlights Zn-doped graphene as a promising candidate for highly selective and sensitive detection of H₂S gas as compared to Cu.

Keywords: Nanosensors & Nanoactuatuators, Nano-biomedicine, Modeling & Simulation
Abstract: In many low-resource settings, particularly rural regions of Ethiopia, postpartum infections remain a leading cause of maternal mortality. Limited access to follow-up care, delays in symptom recognition, and constraints in local clinics make timely diagnosis challenging. This research presents a conceptual framework for an AI-enabled wearable nano-sensor system aimed at improving early detection of postpartum infection through continuous health monitoring. The proposed system consists of a flexible, skin-compatible graphene patch containing dual nano-sensors that continuously monitor body temperature and heart rate at 1 Hz, both early indicators of infection. Physiological signals are transmitted to a low-power edge device connected to a logistic regression AI model, which predicts infection risk as a probability score. Automated notifications are sent to caregivers via email and mock push notifications. A proof-of-concept workflow was implemented using n8n, including steps for manual trigger of sensor data, HTTP POST to the AI model, conditional evaluation of risk, and caregiver alerts. Simulation using 500 publicly available maternal health records demonstrated feasibility in detecting abnormal physiological patterns with high accuracy. The design draws on the researcher’s observations of postpartum care challenges in underserved communities. Currently, the system monitors temperature and heart rate only, excluding other clinical indicators such as discharge odor. Future work could integrate nano-sensors for volatile organic compounds and biosensors for inflammatory markers like C-reactive protein. While high-performance graphene sensors remain costly, this framework identifies opportunities for affordable and scalable alternatives. By combining continuous monitoring, AI-based risk prediction, and automated caregiver notifications, this project provides a concrete example of how the system can operate in practice, bridging conceptual design and technical feasibility for maternal health improvement in low-resource settings.

Keywords: Nanosensors & Nanoactuatuators, Nanomaterials
Abstract: Emamectin Benzoate (EMB), a broad-spectrum insecticide, is widely used in aquaculture and agriculture. It poses health risks to farmers, workers, and consumers. It also causes environmental harm through persistent residues. In this research work, a sensor is developed for EMB detection at room temperature. Green-synthesized Carbon Dots (C-dots) from potato peels are used as active sensing material of the sensor. The sensor was tested with a known concentration of pesticide test sample and it shows an inverse relationship between sensor output and pesticide level. The sensor achieved a maximum response of 64.18 % for a test of 25 µg/ml concentration and the detection limit was found to be 1.22 µg/ml. The sensor showed a consistent repeatability, and a quick response time. The findings of this research reveals that C-dot can be a promising sensing material for reliable and affordable EMB detection across various media promoting environmental safety and public health

Keywords: Nanosensors & Nanoactuatuators, Nanomaterials, Nanofabrication
Abstract: Fast and cost-effective diagnostic techniques are essential for controlling the spread of the SARS-CoV-2 virus. In this work, we present a compact and low-cost biosensor platform based on a planar TiO₂ thin-film substrate coated with a drop-cast Al₂O₃ nanomaterial layer. Probe DNA was immobilized on the surface following chemical functionalization using 3-aminopropyltrimethoxysilane (APTMS) and a glutaraldehyde (GA) cross-linker. High sensitivity was demonstrated through the detection of Cy3-labeled target SARS-CoV-2 DNA via DNA hybridization, achieving a detection limit as low as 10 pM. Compared to the uncoated substrate, fluorescence emission intensity was enhanced by three orders of magnitude due to the increased surface area provided by the Al₂O₃ nanoparticles (NP) and nanowires (NW) coating. Furthermore, nanomaterial-coated ridge waveguides were integrated to enable evanescent wave excitation of fluorophores, showcasing the potential for on-chip photonic biosensing. This porous DNA sensor platform offers a promising approach for highly sensitive and rapid SARS-CoV-2 diagnostics.

Keywords: Nanosensors & Nanoactuatuators, Nanometrology & Characterization, Nano-biomedicine
Abstract: Aptamer-based biosensors offer selective and sensitive detection of illicit drugs by leveraging the specific binding affinity of synthetic oligonucleotides. Atomic force microscopy (AFM) was used to study six drugs, which include marijuana (THC), fentanyl, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), oxycodone, and cocaine. AFM was employed to investigate both morphological and electrical resistivity changes at the nanoscale. Electronic sensors consisting of a nanogap between two gold electrodes coated with aptamers were also used to measure the effect of drugs on the sensors’ capacitance and resistance. Transmission terahertz spectroscopy was then conducted to detect the absorption spectra of each analyte and its corresponding analyte/aptamer complexes. Terahertz probes can be used to scan the sweat on the skin non-intrusively. Bowe-tie structures with nanogap stick-on tattoos can be used on the skin to enhance terahertz interaction with sweat analytes. Our studies reported here are carried out to develop a terahertz probe for detecting analytes and illicit drugs on the skin.

Keywords: Nanosensors & Nanoactuatuators, Nanometrology & Characterization, Nanomaterials
Abstract: Standing wave ultrasonic motors (SWUSMs) utilize the interaction of two resonant modes, typically a bending and an expanding mode, to generate motion. A critical factor in SWUSM performance is the frequency separation between these modes. This paper investigates how preload, an essential assembly-level parameter, influences this frequency separation. The study explores the mechanisms through which preload affects the resonant modes, discuss preload distribution within the PZT element, and evaluates experimental approaches for analyzing preload. Additionally, the impact of preload on motor performance and operation frequency is analyzed for balancing efficiency and stability.

Keywords: Nanofabrication, Nanoelectronics: Emerging material and device challenges in futuristic systems, Nanomaterials
Abstract: Cerium oxide (CeO2) is often used as a lattice-match cap layer for heteroepitaxial growth of REBa2Cu3O7-x (RE: rare earth) superconductors. In this work, we investigated how the nanostructure and grain size of CeO2 heteroepitaxial films on biaxially-textured, coated conductor substrates can be modified via annealing in humid, mixed N2/4%-H2 gas mixtures. X-Ray diffraction (XRD) analysis shows annealing at higher temperatures shifts the lattice constant to lower values. The full-width-half-maximum (FWHM) of omega and phi scans show that the in-plane and the out-of-plane crystallographic texture is relatively unchanged with post-annealing. Surface reconstruction, roughness and grain sizes were characterized using Atomic Force Microscopy (AFM).

Keywords: Nanofabrication, Nanofabrication and Nanomanufacturing for Low-Dimensional Nanomaterials and Nanodevices, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: To realize the potential of superconducting devices, carefully optimized fabrication processes are essential. In this paper, we report on microfabrication via a wet chemical etching process for superconducting films. The film comprised a superconducting EuBa2Cu3O7-δ with 3.4vol% of insulating BaHfO3 nanocolumns at nanoscale intercolumn spacings within the film. The superconducting properties were measured with patterned bridges of varying bridge widths of 25µm, 50µm, 75µm, 100µm, 150µm and 200µm. Electrical transport measurements show that onset of the superconducting transition for the etched bridges was unaffected by chemical etching and was within the experimental accuracy (Δ < 0.6 K). The critical currents Ic measured at 77K (1T - 7T) and 65 K (1T - 7T) show that the Ic results do not vary much for the same measurement temperature and magnetic field, for different bridge widths of the etched superconducting films, indicating that wet chemical etching microfabrication procedure adopted yields consistent results.

Keywords: Nanofabrication, Nano-optics, Nano-photonics & Nano-optoelectronics, Commercializing nanotechnology
Abstract: Patterned high refractive index (HRI) features are frequently used to improve light extraction for displays. [1,2] However, vacuum deposition of HRI coatings can be expensive and difficult over the large display areas required for modern fabrication, and solution-based coatings which can be directly photopatterned are desirable. Direct Optical Lithography of Functionalized Inorganic Nanoparticles, or DOLFIN, offers a pathway for direct coating and patterning of many nanoparticle materials.[3] In this study, we use DOLFIN to pattern TiO2 and ZrO2 nanoparticles and investigate their suitability for patterning light extraction features. Inorganic nanoparticle photoresist formulations have been fabricated from anatase TiO2 and amorphous ZrO2 nanoparticles. Coatings up to 200 nm thick and pattern features down to 2 µm are demonstrated. After annealing, the refractive index of the nanoparticle layer increases and approaches about 65% of the bulk refractive index. Refractive index of 1.92 for TiO2 films and 1.77 for ZrO2 films at 632.8 nm is demonstrated along with patterning of features down to 2 µm resolution.

[1] Park, C.H., Kang, S.W., Jung, SG. et al. Enhanced light extraction efficiency and viewing angle characteristics of microcavity OLEDs by using a diffusion layer. Sci Rep 11, 3430 (2021). [2] Ruth Shinar and Joseph Shinar. Light extraction from organic light emitting diodes (OLEDs), J. Phys. Photonics 4 032002 (2022). [3] Y. Wang, I. Fedin, H. Zhang, and D. V. Talapin, Direct optical lithography of functional inorganic nanomaterials. Science 357, 385–388 (2017).

Keywords: Nanofabrication, Nanometrology & Characterization, MEMS/NEMS
Abstract: Electroplating deposition is a technique that comprises several interesting features and therefore it is widely utilized in diverse applications spanning from automotive to electronics. Because of these, improvements are continuously sough after and modern tools enable the deposition of films with very high quality. Among the various materials, gold attracts important attention in the fields of micro/nano electronics and micro-electro-mechanical (MEMS) systems. Indeed, gold exhibits high conductivity and chemical stability whilst electrodeposited gold membranes are widely utilized as the movable parts in MEMS devices with important interest for Radio Frequency (RF) applications i.e. RF MEMS. In RF applications, electroplating deposition is the preferred one when developing thick membranes typically thicker than 0.5 μm. It is utilized for developing the air bridges or for the devices’ pads. Thinner films are usually deposited by either evaporation or by sputtering mainly because of the low surface roughness typically obtained in these cases. The surface roughness may critically affect the device operation e.g. in RF MEMS by reducing the capacitance or by favoring the onset of field emission currents. On the other hand, electroplating deposition is a low cost method that allows faster deposition and better exploitation of the utilized material thus less wastes that is very important for noble metals. This work aims to present a straightforward experimental study of the surface roughness on thin gold films deposited by electroplating with gradually increasing thickness up to 500 nm. The deposition was performed on glass substrates, using a Cr/Au seed layer deposited by e-gun evaporation. Transmission lines were pattern by standard optical lithography. An Atomic Force Microscopy study of the surface roughness was performed in all cases. The results suggest that the surface roughness increases with the film thickness, remaining though in the order of few nm, comparable to this obtained on evaporated films.

Keywords: Nanomaterials, Nanofabrication and Nanomanufacturing for Low-Dimensional Nanomaterials and Nanodevices, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: In this study, aluminum nitride (AlN) nanostructures were synthesized using a low-cost chemical vapor condensation method based on the direct nitridation of aluminum powder in the presence of ammonium chloride (NH₄Cl). The synthesis was conducted in a triple-zone electric furnace under nitrogen atmosphere. Scanning electron microscopy revealed the successful formation of AlN nanowires with average diameters of ~100 nm and lengths of several micrometers. Photoluminescence spectroscopy, performed at room temperature using a 325 nm excitation source, showed broad visible emissions These findings suggest that the synthesized AlN nanostructures hold promise for future optoelectronic applications, particularly in light-emitting devices.

Keywords: Nanopackaging
Abstract: Fan-out packaging addresses several challenges with traditional packaging. These include direct assembly to system substrates and boards while eliminating off-chip solder interconnects with large stand-off height, along with the minimization of wafer bumping needs. In addition, fan-out packaging offers superior electrical performance, along with extension to 3D package stacking for vertical system integration. For low Input/Output (I/O) termination count between the chip and substrate, additively-deposited fan-out interconnects are of high interest. Traditional approaches are based on silver paste or ink deposits for interconnects. We investigate solder-graphene composite-based fan-out interconnects as an alternative to silver. In order to facilitate, solder trace formation on polymer gap-fill, graphene network loading is introduced into the solders. Initial process development showed the feasibility of the formation of such interconnects. This material system also has a strategic role in phase-change materials for heat-spreading, electromagnetic interference shielding and other applications. The second part of the paper described innovative multiscale fan-out packages with solder composite-based interconnects as an extension of today’s glass or laminate-based panel fan-out packages.

Keywords: Modeling & Simulation, Spintronics, Nanomagnetics
Abstract: We have discussed the hole-induced magnetic solitons and hole-induced insulator-metal transition in manganites by using the gauge-invariant Lagrangian density and the path-integral method. The anomalous transport properties of manganites LaCaMnO are analyzed from the standpoint of the percolation-like dynamics of hole-induced magnetic solitons and the random resister network. In addition, we have argued the relation to the theoretical formula of high Tc cuprates.

Keywords: Modeling & Simulation, Nanomaterials
Abstract: This paper investigates the effect of using aged nano-silica plus micro-alumina trihydrate on the electric field distribution of 33kV outdoor polymeric insulators subjected to lightning conditions. A 33kV overhead line in Arua district, Uganda was modeled in LIOV-EMTP and a lightning first stroke was subjected near the line at distances of 15m, 30m, 50m, and 100m. Three polymeric insulator that is, suspension, line-post, and pin insulators were modeled in COMSOL Multiphysics and the dielectric constants after aging of neat silicone rubber (SAT-0) and silicone rubber filled with nano-silica plus micro-alumina trihydrate (SAT-6) were used as material input. The peak voltages obtained in LIOV-EMTP were subjected to each insulator high voltage end with the ground end at 0V. In LIOV-EMTP, the magnitude of induced voltages reduced with increase in lightning strike distance. The results in COMSOL revealed that the suspension insulator exhibited the highest maximum electric field while the line-post insulator exhibited the lowest when the dielectric constants of SAT-0 and SAT-6 are used. The line-post insulator experienced the highest average electric field while the suspension insulator experienced the lowest. The change in the dielectric constant of SAT-0 to SAT-6 had minimal effect on the insulator average electric field. The line-post insulator had the lowest field enhancement factor while the suspension insulator had the highest. The % change in the field enhancement factor ranged from +3.38% to +3.72%, -1.88% to -2.58%, and +5.77% to +6.5% for the pin, line-post, and suspension insulators respectively. The results indicate that the geometry of the insulator greatly influences the electric field distribution and should be considered together with the material improvements when designing 33kV outdoor insulators.

Keywords: Modeling & Simulation, Nanofabrication, Nanomaterials
Abstract: In this work we present a forming-free unipolar switching, volatile conductive bridge RAM device on a vertically aligned quasi-2D halide perovskite ( PEA_2MA_4Pb_5I_{16}), replacing the oxide layer commonly used in typical resistive type memristors. The device exhibits threshold-triggered spiking and synaptic plasticity, enabling neuromorphic functions such as integrate-and-fire behaviour and paired-pulsed facilitation/depression. Fabricated via a humidity-tuned solvent engineering process, the perovskite film supports directional ionic transport, resulting in fast, low-power (I < 10^{5} A) switching. Application potential of the device is explored by developing a compact drift-diffusion-thermal model incorporating dose-dependent adaptation, reproducing key dynamics and neural plasticity evolution. Compared to conventional resistive RAMs, this architecture stands as a promising alternative for application in unconventional computing paradigms, due to their improved volatility and bio-interfacing potential, thus supporting their use as spiking neuromorphic elements in neuromorphic computing and hybrid bioelectronic systems.

Keywords: Nanosensors & Nanoactuatuators, Modeling & Simulation
Abstract: Tactile sensors play an important role in technological advancements by enabling better human-machine interaction and sensing. Many of the advanced applications require material recognition in addition to sensing. In this work, a novel and simple solution to classification and identification of materials based on touch using graphene based flexible capacitive tactile sensors is presented. The sensor utilizes the different capacitance responses upon touch by different materials (conducting and nonconducting) combined with an approach based on artificial neural network (ANN) to classify different materials. The integration of machine learning algorithm to classify objects with a classification accuracy of 84.57% is achieved. A real-time accurate object recognition is also demonstrated as an application. This demonstration of accurate tactile sensors possessing material recognition is expected to accelerate progress in semiconductor and electronics technologies.

Keywords: Quantum, Neuromorphic & Unconventional Computing, Spintronics, Nanomaterials
Abstract: We present experimental results of electron transport in one-dimensional (1D) quantum channels created electrostatically with a triple-gate setup on GaAs/AlGaAs heterostructures. In this configuration, two gates determine the confinement potential, while the third gate adjusts the carrier density within the 1D channel. While maintaining a shallower confinement and decreasing the 1D carrier density, we observe interactions between the ground and first excited states, leading to an anticrossing. These states rely on the 1D carrier density, the decrease in confinement potential, and the effects of Coulomb interaction. Our results suggest that fine-tuning the triple-gate geometry may reveal complex phases in interacting 1D quantum systems.

Keywords: Quantum, Neuromorphic & Unconventional Computing
Abstract: The breakdown characteristics of SiNx layers with different stoichiometries are explored. The stoichiometry of SiNx is modified by changing the gas flow rates during the LPCVD deposition. These layers are suitable for RRAM cells.

Keywords: Spintronics, Nanomaterials, Nanometrology & Characterization
Abstract: Magnetic symmetry of Tb and Co0.6Fe0.4 co-sputtered for applications in ultrafast spintronic technologies Dereje Seifu1, Dario Arena2, and Enrique Del Barco3 1Physics Department, Morgan State University, Baltimore, Maryland, USA 2Physics Department, University of South Florida, Tampa, Florida, USA 3Physics Department, University of Central Florida, Orlando, Florida, USA

Rare-earth doped magnetic alloys are promising for potential applications in low-power ultrafast spintronic technologies due to the low symmetry and large spin-orbit coupling. [1] Ultrafast spintronic technologies are spin-based electronics where the control and manipulation of electron spin occur on timescales ranging from picoseconds to femtoseconds. [2] These technologies enhance data processing and storage beyond the current speed limit of conventional electronics by using the quantum properties of electron spin. [3] Here, we present a synthesis of Tbx(Co0.6Fe0.4)1-x, achieved through magnetron DC and RF sputtering, which offers industry-friendly benefits, including faster deposition at medium energy, cost-effectiveness, and scalability. The surface morphology of the film was characterized using TEM, identification and quantification of the elements was carried out using EDS, the lattice was scanned using SAED, and magnetic properties were studied using VSM at several angles between the sample normal and the magnetic field.

References [1] Chen, Q., Guo, Q., Huang, Z., Fang, B., Li, S., Lv, W., Li, R., Luo, Y., Du, J., Zhang, B. and Zhai, Y.. (2023). Journal of Alloys & Compounds, 930, p.167351. [2] Chen, Z., Li, S., Zhou, S., Lai, T. (2019). New Journal of Physics, 21(12), 123007. [3] González, J. A., Andrés, J. P., López Antón, R. (2021). Applied trends in magnetic rare earth/transition metal alloys and multilayers. Sensors, 21(16), 5615.

Acknowledgements The authors would like to acknowledge AFOSR and US AFRL Grant # FA9550-24-1-0290. One of the authors, DS, would also like to acknowledge the United States Department of Defense Center of Excellence for Advanced Electro-photonics with 2D materials - Morgan State University, under Grant #W911NF2120213

Keywords: Fundamentals and applications of nanotubes, nanowires, quantum dots and other low dimensional materials, Nanoenergy, Environment & Safety, Nanometrology & Characterization
Abstract: Electrochemical anodization in fluoride-bearing ethylene glycol (EG)-based electrolytes has been used to grow vertically oriented, self-organized nanotube and nanopore arrays in a range of semiconducting transition metal oxides including, but not limited to, TiO2, Ta2O5, ZrO2, WO3, ZnO, VO2 and Nb2O5. The resulting metal oxide nanotube arrays (MONTAs) have been used as photocatalysts in artificial photosynthesis to split water (generating H2 in the process) and photoreduce CO2 using H2O. The photocatalytic activity of MONTAs is dependent on the surface adsorbate structure that forms when reactants such as CO2 and H2O physisorb or chemisorb on the surfaces of MONTAs. It has recently come to attention that the nature of the anodization electrolyte determines the number and type of low coordinate reactive sites on the surface of MONTAs, which in turn controls the surface binding mode of chemisorbed reactants and thus influences charge transfer steps in photocatalytic and electrocatalytic reactions. The adsorbate structure in TiO2 nanotube arrays (TNTAs) grown in formamide-based electrolyte consisted of physisorbed and chemisorbed carbon monoxide (CO) along with linearly adsorbed CO2 and various monodentate and bidentate carbonate species. The observation of adsorbed CO in the dark is unusual and specific to formamide-grown TNTAs. Such an observation implies spontaneous deoxygenation of CO2 and points to the carbon dioxide anion radical (a critical intermediate) formation bottleneck being overcome. Formamide-grown TNTAs produced 18.44 μmol g−1h−1 of CO during vapor phase CO2 photoreduction under AM1.5G solar illumination and outperformed EG-grown TNTAs by a factor of 1.7. Nb2O5 nanotube arrays grown in formamide-based electrolyte produced 70 μmol g−1h−1 of H2 from triethanolamine-containing aqueous solutions under low intensity ultraviolet illumination. These results will be discussed in the context of the high dielectric constant and high boiling point of formamide-based electrolytes providing specific advantages over EG-based electrolytes in the growth of MONTAs.

Keywords: Fundamentals and applications of nanotubes, nanowires, quantum dots and other low dimensional materials, Nanoenergy, Environment & Safety, Nanometrology & Characterization
Abstract: Bismuth oxyhalides (BiOX) are a family of two-dimensional (2D), ternary, layered nanomaterials composed of earth-abundant elements: bismuth, oxygen, and halogens. BiOX nanosheets are well-suited for harvesting renewable energy through sunlight-driven photocatalysis due to short charge carrier diffusion distances, higher specific surface area, efficient in-plane charge transport, built-in electric fields, and tunable bandgaps. Because of the van der Waals interactions intrinsic to layered BiOX materials, other 2D materials such as carbon nitride (CN) can be integrated with them, enhancing the generation and separation of charge carriers at the heterointerface. BiOX solid solutions (e.g. BiOBrxI1-x) offer a versatile platform to tailor the bandgap and modify the conduction and valence band edges, thereby modulating the thermodynamic driving force available for driving chemical redox reactions. A nanostructured heterojunction consisting of BiOI and fluorine-doped, chlorine-intercalated carbon nitride (CNF-Cl) was formed by solvothermal synthesis and delivered promising performance as a photoanode in photoelectrochemical (PEC) water splitting. A more optimized version of this heterojunction, namely BiOI nanosheets integrated with few-layered g-C3N4 exhibited enhanced PEC water splitting performance with a photocurrent density of 1.3 mAcm-2 under AM1.5G one sun illumination, attributed to a type-II charge transfer mechanism and suppressed inter-layer charge recombination. BiOBrxI1-x solid solutions demonstrated adjustable band energetics, increased surface area, and mitigated exciton-phonon interactions. The solid solution behavior was investigated using 209Bi solid-state NMR spectroscopy, with additional confirmation provided by Vegard’s law through the refinement of lattice parameters. The optimized solid solution produced a photocatalytic H2 yield of 16.32 µmolg-1h-1 due to an increased number of reaction sites, and enhanced electron density. Furthermore, a ternary heterojunction of BiOBr/Bi2WO6/Bi2S3 was synthesized by an in-situ solvothermal method followed by ultrasound-assisted synthesis. The ternary heterojunction demonstrated a solar-to-hydrogen (STH) conversion efficiency >3%.

Keywords: Nanomaterials, Nano-optics, Nano-photonics & Nano-optoelectronics
Abstract: We report the first experimental measurement of the optical out-of-plane surface conductivity in bilayer graphene.[1] Out-of-plane optical constants of 2D materials are experimentally elusive because the substrate on which 2D materials are deposited hides the contribution of the out-of-plane constants to their optical response.[2] Until now only the observation of the out-of-plane surface susceptibility of monolayer graphene was reported.[3] We adopt an experimental approach that consists in two steps[1]. The first is a standard ellipsometric measurement on a bilayer graphene sample, deposited on a transparent polydimethylsiloxane (PDMS) substrate. In a second step, we remove the substrate contribution. We place the same sample in a prism-shaped mold, we pour non-polymerized PDMS on it and wait for complete polymerization. Owing to the replicant properties of PDMS we obtain a bilayer graphene totally immersed in the PDMS prism without spurious interfaces. In this second step, the light reflected from the sample is much less than in the previous experiment. This forced us to develop a homemade ellipsometric setup working at a 633 nm. Our experiment produces 4 experimental data, Δs and Ψs from the sample deposited on the PDMS substrate and Δi and Ψi from the immersed sample (Figure 1). From these it is possible to obtain the in-plane and the out-of-plane surface susceptibilities (χ∥,χ⊥) and surface conductivities (σ∥,σ⊥). Results are reported in Table 1, that compares them with those obtained for the monolayer[1] and for bulk graphite.[4] We note that χ∥ and σ∥ for the bilayer are practically equal to the values measured for monolayer graphene and for bulk graphite. This result is confirmed by a lot of other experimental studies.[5] Out-of-plane optical constants behave differently, as they are shown to increase with increasing number of layers. This is the main result presented here.

Keywords: Nanomaterials, Nanoelectronics: Emerging material and device challenges in futuristic systems
Abstract: Ferroelectric tunnel junctions (FTJs) have attracted significant attention over the past decades due to their potential as nonvolatile memory devices, offering high storage density, low power consumption, and fast operation speed. Concurrently, the growing demand for high-performance memory has driven the development of oxide heterostructures, which enable multifunctionality and can be modulated through various degrees of freedom. It is well established that the electronic and physical properties of oxide interfaces are strongly influenced by interfacial structure and band alignment. However, strategies to introduce new functionalities into FTJs remain limited. In this work, we report a novel photovoltaic effect in FTJs employing BaTiO₃ as the ferroelectric barrier layer. Notably, this effect is highly sensitive to the interfacial termination. The photovoltaic response is observed exclusively in FTJs grown on SrO-terminated Nb-doped SrTiO₃ (NSTO) substrates when the devices are in the OFF state, whereas no such effect is present in devices grown on TiO₂-terminated NSTO. Synchrotron test shows a smaller indirect band gap appear in the SrO-terminated samples. This unexpected direct to indirect band gap transition plays important roles for PV formation as it can reduce electron-hole radiative recombination. This termination-dependent photovoltaic behavior underscores the critical role of interface engineering in oxide-based electronics. Moreover, this discovery offers a promising pathway for non-destructive readout in multilevel memory applications.

Keywords: Nanomaterials, Nanofabrication and Nanomanufacturing for Low-Dimensional Nanomaterials and Nanodevices, Nanoenergy, Environment & Safety
Abstract: In this work, we report a novel microwave-assisted solvothermal route for the rapid synthesis of Cu(In,Ga)Se₂ (CIGS) nanoparticles with controlled morphology and composition, aimed at printable photovoltaic applications. The synthesis was carried out using a polymer-assisted strategy, where a stabilizing polymer was introduced to control particle growth and dispersion during the reaction. The use of microwave irradiation significantly reduced the synthesis time compared to conventional solvothermal methods, achieving well-crystallized CIGS nanoparticles in under 30 minutes.

Structural and compositional analysis was performed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The resulting nanoparticles exhibited average diameters of approximately 20 nm, suitable for formulation into printable pastes. To enable further processing for optoelectronic applications, the CIGS nanoparticles were successfully dispersed in a polyethylene glycol (PEG) matrix, forming a stable and homogeneous paste. This formulation can be potentially used for low-cost, solution-based fabrication of thin-film solar cells.

The enhancement in reaction kinetics is attributed to the volumetric heating and rapid energy transfer provided by microwave irradiation, which accelerates nucleation and growth of nanoparticles while maintaining narrow size distribution. Microwave energy interacts directly with the solvent and the precursor complex, generating localized superheating and high-pressure conditions that are difficult to achieve with conventional heating. This mechanism not only reduces the reaction time but also improves reproducibility and energy efficiency. These results demonstrate the potential of microwave-assisted solvothermal synthesis in producing high-quality CIGS nanoparticles suitable for printed photovoltaic devices, paving the way for scalable and sustainable solar technologies.

Keywords: Fundamentals and applications of nanotubes, nanowires, quantum dots and other low dimensional materials, Nanofabrication and Nanomanufacturing for Low-Dimensional Nanomaterials and Nanodevices, Nanoenergy, Environment & Safety
Abstract: Carbon nitride (CN) is a layered polymeric semiconductor, which is composed of tris-s-triazine units linked together with tertiary nitrogen. Nanosheets of CN are 2D materials. While the composition of conventional CN is C3N4, the ratio of C:N is controllable through synthesis and doping. CNs are outstanding photocatalysts, photoelectrodes and charge transport layers. CNs also exhibit remarkable thermal, photochemical and ambient stability and durability, making them attractive alternatives to small molecule organic semiconductors and typical conjugated polymers. The electronic bandgap (Eg) of 2.7 eV for C3N4 is too wide to efficiently harvest sunlight. Doping with main group elements is a feasible method to address the above-mentioned shortcomings through the donation of one or more lone pairs to the heteroaromatic ring system of CN. Doping with F and P narrows the bandgap as does increasing the ratio of N:C. The Eg for P-doped C3N4 is 2.1 eV while C3N5 has an Eg value of 1.7 eV. S and Se alter the photophysics of CN. Doped CNs can be used as sensitizers for metal oxides (e.g. TiO2) and plasmonic nanoparticles in heterojunction photoanodes. TiO2 nanotube arrays decorated with P-doped carbon nitride quantum dots (P:CNQDs) exhibit photocurrent densities > 2.5 mA/cm2 and a hydrogen evolution rate > 20 µmol/h in photoelectrochemical (PEC) water-splitting under AM1.5G simulated sunlight. Carbon-rich carbon nitride nanoparticles (CNNPs) can be used to optically pump the LSPR of Au NPs through resonance energy transfer to achieve PEC current densities >3 mA/cm2. C3N5 and doped C3N4 have been used as electron transport layers (ETLs) and hole transport layers (HTLs) in high efficiency perovskite solar cells and organic photovoltaics. In conjunction with silver nanoparticles of different shapes, various types of doped carbon nitrides are able to conduct the visible light-driven reduction of 4-nitrobenzenethiol (4-NBT) to dimercaptoazobenzene (DMAB).