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2025

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Full-Text Articles in Semiconductor and Optical Materials

Two Members Of The Editorial Board Of Journal Electrochemistry, Kai Wu Elected As An Academician Of The Chinese Academy Of Engineering And Yi Cui A Foreign Academician Of The Chinese Academy Of Sciences, Editorial Office Of J.Electrochem. Dec 2025

Two Members Of The Editorial Board Of Journal Electrochemistry, Kai Wu Elected As An Academician Of The Chinese Academy Of Engineering And Yi Cui A Foreign Academician Of The Chinese Academy Of Sciences, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Electrochemical Characterization And Modulation Of Biological Processes, Yue-Qi Li, Wei-Hua Huang, De-Chen Jiang, Bao-Hong Liu, Bin Su, Yang Tian, Jing-Juan Xu, Ping Yu, Feng Zhao, Huang-Xian Ju, Jing-Hong Li Dec 2025

Electrochemical Characterization And Modulation Of Biological Processes, Yue-Qi Li, Wei-Hua Huang, De-Chen Jiang, Bao-Hong Liu, Bin Su, Yang Tian, Jing-Juan Xu, Ping Yu, Feng Zhao, Huang-Xian Ju, Jing-Hong Li

Journal of Electrochemistry

Electrochemical processes lie at the core of biological function, governing energy transduction, metabolic flux, and molecular signaling. Recent advances in electrochemical science now allow these processes to be probed and controlled with unprecedented spatial, temporal, and chemical resolution. In this review, we present an integrated framework that progresses from fundamental mechanisms to analytical technologies and functional modulation. We begin by outlining electron transfer pathways in mitochondrial respiration, microbial extracellular electron transfer, and DNA- and protein-based charge conduction, followed by the principles of photon-electron conversion in photosynthesis and the central role of redox equilibrium in coordinating cellular responses. We then highlight …


Journal Of Electrochemistry Officially Indexed By Leading Oa Databases Oarl And Coaj, Editorial Office Of J.Electrochem. Dec 2025

Journal Of Electrochemistry Officially Indexed By Leading Oa Databases Oarl And Coaj, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


Feature Column Of Journal Of Electrochemistry Nominated For 2025 Top 10 Famous Columns Of Fujian Provincial Newspapers And Periodicals, Editorial Office Of J.Electrochem. Dec 2025

Feature Column Of Journal Of Electrochemistry Nominated For 2025 Top 10 Famous Columns Of Fujian Provincial Newspapers And Periodicals, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.


An Overview Of Biomass-Derived Graphene Oxide And Its Characteristics For Future Sustainable Applications, Afif Wardana, Ahmad Nabil Shahab, Donanta Dhaneswara, Nofrijon Sofyan Dec 2025

An Overview Of Biomass-Derived Graphene Oxide And Its Characteristics For Future Sustainable Applications, Afif Wardana, Ahmad Nabil Shahab, Donanta Dhaneswara, Nofrijon Sofyan

Journal of Materials Exploration and Findings

The production of graphene oxide (GO) from biomass presents considerable promise as a sustainable alternative substitute for traditional semiconductors. Biomass waste, abundant and often underutilized worldwide, is distinguished by its high carbon content and regenerative characteristics, rendering it an optimal resource for sustainable material production. By heating its biopolymers, lignocellulosic biomass can be used as a new material to make graphene, which forms three-dimensional turbostratic crystallites. These crystallites, composed of partially defective aromatic carbon sheets with graphite-like characteristics, make it easier to create GO with specialized functions for cutting-edge applications. Its capability underscores the revolutionary potential of biomass waste in …


Test Data: Raised Or Recessed? Finding The Optimal Gate Architecture For Improving The Static Performance Of Graphene Transistors, Ivan Puchades, Tzu-Jung Huang, Andrew Spencer, Luke Ingraham, Anibal Pacheco Nov 2025

Test Data: Raised Or Recessed? Finding The Optimal Gate Architecture For Improving The Static Performance Of Graphene Transistors, Ivan Puchades, Tzu-Jung Huang, Andrew Spencer, Luke Ingraham, Anibal Pacheco

Data

As silicon CMOS technology approaches its scaling limits, graphene offers a compelling alternative as the active material channel in transistors due to its high carrier mobility and atomically thin profile, which provide strong electrostatic control and promise high-performance analog applications. However, roadblocks such as device-to-device variation, high contact resistance, poor dielectric interfaces, and non-uniform graphene quality have limited the adoption of graphene field effect transistors (GFETs). Hence, further investigations are required for mitigating these issues at a material, e.g., by improving graphene transfer, and device level, e.g., by finding an appropriate gate architecture. In this work, we directly compare two …


Development Trends And Priority Research Fields Of Electrochemical Discipline In The 15th Five Year Plan Period, Lin Zhuang, Wen-Bin Cai, Heng-Xing Ji, Qing Li, Gong-Wei Wang, Sen Xin, Qing Zhao, Fang-Yi Cheng, Yu-Guo Guo, Lan-Qun Mao, Yang Tian, Fei Wu, Li-Min Zhang, Yan Xiang, Jin-Song Hu, Rui Cao, Li Xiao, Hua-Bing Tao, Wei Xing, Dong-Ping Zhan, Hong-Gang Liao, Mei-Ling Xiao, Bin Ren, Zhang-Quan Peng, Rui Wen, Xiang Wang, Yue-Feng Song, Hou-Fu Lv, Bao-Yu Xia, Guo-Xiong Wang, Jun Cheng, Zhi-Pan Liu, Min Zhou, Bing Huang, Cun-Pu Li, Yu-Qin Zou, Shuang-Yin Wang, Hai-Bo Lin, Zi-Dong Wei Oct 2025

Development Trends And Priority Research Fields Of Electrochemical Discipline In The 15th Five Year Plan Period, Lin Zhuang, Wen-Bin Cai, Heng-Xing Ji, Qing Li, Gong-Wei Wang, Sen Xin, Qing Zhao, Fang-Yi Cheng, Yu-Guo Guo, Lan-Qun Mao, Yang Tian, Fei Wu, Li-Min Zhang, Yan Xiang, Jin-Song Hu, Rui Cao, Li Xiao, Hua-Bing Tao, Wei Xing, Dong-Ping Zhan, Hong-Gang Liao, Mei-Ling Xiao, Bin Ren, Zhang-Quan Peng, Rui Wen, Xiang Wang, Yue-Feng Song, Hou-Fu Lv, Bao-Yu Xia, Guo-Xiong Wang, Jun Cheng, Zhi-Pan Liu, Min Zhou, Bing Huang, Cun-Pu Li, Yu-Qin Zou, Shuang-Yin Wang, Hai-Bo Lin, Zi-Dong Wei

Journal of Electrochemistry

In fulfillment of the national science-and-technology development agenda, the Department of Chemical Sciences of the National Natural Science Foundation of China (NSFC) convened the Strategic Symposium on the Fifteenth Five-Year (2026–2030) Development Plan for Electrochemistry held in Xiamen on 29 August, 2025—the culminating year of the Fourteenth Five-Year (2021–2025) Development Plan. More than forty leading experts in the field of electrochemistry participated with spanning nine thematic fronts: Interfacial Electrocatalysis, Interfacial Electrochemistry for Energy Storage, Bioelectrochemistry, Electrochemistry of Hydrogen Energy, Electrochemical Micro-/Nano-Manufacturing, Operando Electrochemical Characterization, Electro-Thermal Coupling Catalysis, Theoretical and Computational Electrochemistry, and Electrochemical Synthesis. The forum assembled China’s foremost electrochemical …


Intrinsic Defects (Vacancies And Antisites) In Neutron Irradiated Cdsip2 Crystals, Timothy D. Gustafson, Elizabeth M. Scherrer, Nancy C. Giles, Kevin T. Zawilski, Peter G. Schunemann, Jonathan E. Slagle, Kent L. Averett, Larry E. Halliburton Oct 2025

Intrinsic Defects (Vacancies And Antisites) In Neutron Irradiated Cdsip2 Crystals, Timothy D. Gustafson, Elizabeth M. Scherrer, Nancy C. Giles, Kevin T. Zawilski, Peter G. Schunemann, Jonathan E. Slagle, Kent L. Averett, Larry E. Halliburton

Faculty Publications

Cadmium silicon phosphide (CdSiP2) is a nonlinear optical material widely used in optical parametric oscillators. Intrinsic defects (vacancies and antisites) are responsible for unwanted broad optical absorption bands in these crystals that degrade the performance of the devices. In the present work, optical absorption and electron paramagnetic resonance (EPR) spectra are acquired (at room temperature and 12 K, respectively) from a neutron-irradiated CdSiP2 crystal. After the irradiation, the crystal is highly absorbing from the band edge near 600 nm to beyond 1.3 μm because of overlapping defect-related absorption bands. Heating to 550 °C removes nearly all the …


Unified Study Of The Classical Hall Effect, Carter J. Reed, Javier E. Hasbun, Wyatt E. Ackerman, L Ajith Desilva Sep 2025

Unified Study Of The Classical Hall Effect, Carter J. Reed, Javier E. Hasbun, Wyatt E. Ackerman, L Ajith Desilva

Georgia Journal of Science

Germanium (Ge) samples with different doping types, acceptors (p-type) and donors (n-type), were studied to investigate charge carrier behavior. Carrier concentrations were found to be 1.16×10^21 m^(-3) for the p-type sample and 7.337×10^20 m^(-3) for the n-type sample. These experiments were conducted for the standard Hall effect (Hall voltage versus low magnetic field (B) values) as well as conductivity and Hall voltage versus temperature for different B-fields. The measurements versus temperature at zero-field allow us to obtain band gap ( Eg). While we investigate the conductivities for n-type and p-type doped samples, we also study the conductivity of an undoped …


Effect Of Saccharin On Crystallization Behavior Of Electroless Cobalt Plating, Yu-Xin Luo, Jing-Jing Wang, Lu Wang, Zi-Yi Yan, Yi Ma, Xin Bo, Jing-Shuang Dang, Zeng-Lin Wang Aug 2025

Effect Of Saccharin On Crystallization Behavior Of Electroless Cobalt Plating, Yu-Xin Luo, Jing-Jing Wang, Lu Wang, Zi-Yi Yan, Yi Ma, Xin Bo, Jing-Shuang Dang, Zeng-Lin Wang

Journal of Electrochemistry

In the process of electroless cobalt plating, the saccharin additive can significantly change the surface morphology, texture orientation, and conductivity of the cobalt coating layer. When the amount of saccharin was 3 mg·L–1, the cobalt coating transformed from disordered large grains to a honeycomb structure, with a preferred orientation of (002) facet on hexagonal close-packed (HCP) cobalt crystals. The resistivity of the cobalt film decreased to 14.4 μΩ·cm, and further decreased to 10.7 μΩ·cm after the annealing treatment. When the concentration of saccharin was increased, the grain size was gradually refined and a “stone forest” structure was observed, …


First Principles Materials Discovery And Design For Photovoltaic And Solar Thermal Alloys Using High Throughput Methods, Andrew Pike Aug 2025

First Principles Materials Discovery And Design For Photovoltaic And Solar Thermal Alloys Using High Throughput Methods, Andrew Pike

Dartmouth College Ph.D Dissertations

Materials selection has been a challenge since the dawn of time. With the advent of computational methods and high throughput databases, materials can be discovered and assessed before they are even synthesized. In this thesis I will discuss my work towards designing new materials for clean energy uses, especially alloys which have been underexplored from computational methods. To begin, I present a case study explaining the synthesis of the Yb14ZnSb11 thermoelectric material. Next, I explore the class of AM2Pn2 Zintl materials. From the previously identified BaCd2P2, it is suspected that …


Synthesis, Structural Characterization And Optical Studies Of Silver-Indium-(Zinc)-Chalcogenide Fluorescent Quantum Dots, Sujal Acharya Aug 2025

Synthesis, Structural Characterization And Optical Studies Of Silver-Indium-(Zinc)-Chalcogenide Fluorescent Quantum Dots, Sujal Acharya

Graduate Theses and Dissertations

Developing a non-toxic, high-performance fluorescent nanomaterial is crucial for overcoming the environmental and health restrictions of current cadmium, and lead based quantum dots (QDs), which limit the application of quantum dots in optoelectronics and bioimaging. In this thesis, we synthesized environmentally friendly AgInS2 QDs by a colloidal method, systematically altering the In/Ag precursor ratio from 2 to 6 to study the impact on their optical and photophysical properties. Our goals were to find the optimal stoichiometry for maximum quantum efficiency and stability. We also investigated further improving optical and photophysical properties through shelling with ZnS. The emission spectra appeared broad, …


Discovering And Designing Novel Perovskite Photovoltaic Materials Via Machine Learning, Junyeong Ahn Jul 2025

Discovering And Designing Novel Perovskite Photovoltaic Materials Via Machine Learning, Junyeong Ahn

Discovery Undergraduate Interdisciplinary Research Internship

Perovskite semiconductors are promising materials for high-efficiency photovoltaics due to their outstanding optoelectronic properties, emerging as a sustainable energy source through solar cell applications. Perovskites with the ABX₃ composition (A, B = metal or organic cations with varying oxidation states; X = chalcogen or halogen anions) have gained interest for their excellent phase stability and compositional tunability. However, combinatorial possibilities arising from the many choices of A, B, and X site species, and their respective mixing fractions, a large number of possible ABX₃ perovskites remain undiscovered. In this work, we used machine learning (ML) methods to design new stable and …


Preparation And Characterization Of Electrospun Pvdf-Based Nanocomposite Fibers For Energy Harvesting And Storage Applications, Ahmed Ramzy, Electrochemistry And Corrosion Laboratory, Physical Chemistry Department, National Research Centre, Dokki, Cairo, 12622, Egypt, Ahmed M. El-Mahalawy Jul 2025

Preparation And Characterization Of Electrospun Pvdf-Based Nanocomposite Fibers For Energy Harvesting And Storage Applications, Ahmed Ramzy, Electrochemistry And Corrosion Laboratory, Physical Chemistry Department, National Research Centre, Dokki, Cairo, 12622, Egypt, Ahmed M. El-Mahalawy

Nanotechnology Research Centre

This study introduces the development of multifunctional electrospun polyvinylidene fluoride (PVDF) composite films doped with potassium octatitanate (KTO) for advanced energy applications. The research tackles key challenges in energy generation and storage through innovative material design and detailed characterization. Adding 0.2 wt% KTO to PVDF electrospun fibers resulted in a notable increase in crystallinity to 78.51 %, marking a significant enhancement in material properties. Structural analysis using X-ray diffraction and Fourier transform infrared spectroscopy confirmed optimal phase composition, while morphological features were verified through field emission scanning electron microscopy. The composite films showed exceptional electrochemical performance, with bulk electrolyte resistance …


Vacuum Consistent Electrochemistry In Ionic Liquid Combined With Oxide Epitaxy, Yuji Matsumoto Jun 2025

Vacuum Consistent Electrochemistry In Ionic Liquid Combined With Oxide Epitaxy, Yuji Matsumoto

Journal of Electrochemistry

We introduce our state-of-the art of “vacuum consistent electrochemistry” to an investigation of the interfaces between oxides and ionic liquid (IL). Pulsed laser deposition (PLD) has been one of the powerful and sophisticated techniques to realize nanoscale preparation of high-quality epitaxial oxide thin films. On the other hand, electrochemistry is a simple, very sensitive, and non-destructive analysis technique for solid-liquid interfaces. To ensure the reproducibility in experiment of the interfaces of such epitaxial oxide films, as well as bulk oxide single-crystals, with IL, we employ a home-built PLD-electrochemical (EC) system with IL as an electrolyte. The system allows one to …


Pm Irras Studies Of Organized Molecular Films At A Gold Electrode Surface, Zhang-Fei Su, Ai-Cheng Chen, Jacek Lipkowski Jun 2025

Pm Irras Studies Of Organized Molecular Films At A Gold Electrode Surface, Zhang-Fei Su, Ai-Cheng Chen, Jacek Lipkowski

Journal of Electrochemistry

This feature article illustrates the potential of polarization modulation infrared reflection absorption spectroscopy (PM IRRAS) to provide molecular-level information about the structure, orientation and conformation of constituents of thin films at electrode surfaces. PM IRRAS relies on the surface selection rules stating that the p-polarized IR beam is enhanced, while the s-polarized beam is attenuated at the metal surface. The difference between p- and s-polarized beams eliminates the background of the solvent and provides IR spectra at a single electrode potential. In contrast, two other popular in situ IR spectroscopic techniques, namely, subtractively normalized interfacial Fourier transform infrared spectroscopy (SNIFTIRS) …


Redox-Active Monolayers On Ito Prepared By Post-Amidation And Direct Esterification And Their Spectroelectrochemical Characterization, Takamasa Sagara, Sae Nakai, Ryusuke Yofu, Shota Kojin Jun 2025

Redox-Active Monolayers On Ito Prepared By Post-Amidation And Direct Esterification And Their Spectroelectrochemical Characterization, Takamasa Sagara, Sae Nakai, Ryusuke Yofu, Shota Kojin

Journal of Electrochemistry

A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing. The necessity for its sophistication arises from the availability of multi-dimensional sensing signals. Simultaneous monitoring of the redox current and color change synchronized with the oxidation state change significantly enhances sensitivity and selectivity. This study aimed to elucidate the modification of an indium tin oxide (ITO) electrode with a viologen monolayer with an ordered orientation. Novel methods were developed to immobilize a viologen molecule bearing a carboxyl group to form assembled monolayers through a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide with N-hydroxy-succinimide (EDC/NHS). In the two methods …


Colloidal Quantum Dots: A Path Toward Making Mid-Wave Infrared Sensing A Ubiquitous Technology, Mohammad Mostafa Al Mahfuz May 2025

Colloidal Quantum Dots: A Path Toward Making Mid-Wave Infrared Sensing A Ubiquitous Technology, Mohammad Mostafa Al Mahfuz

Dissertations

Reducing the size, weight, power consumption, and cost (SWaP-C) of infrared detectors could make infrared sensing more widely accessible. In the critical mid-wavelength infrared (MWIR) spectral range of 3-5 gm, commercially available detectors are limited by the high costs associated with epitaxial growth and hybridization, as well as the need for cryogenic cooling. These factors restrict their use to defense and space applications.

Colloidal quantum dots present a promising material for overcoming these challenges, with wafer-scale monolithic integration and Auger suppression being the key material capabilities to minimize the sensor's SWaP-C. Infrared sensors based on colloidal quantum dots have been …


Theoretical Insights Into The Atomic And Electronic Structures Of Polyperyleneimide: On The Origin Of Photocatalytic Oxygen Evolution Activity, Yi-Qing Wang, Zhi Lin, Ming-Tao Li, Shao-Hua Shen May 2025

Theoretical Insights Into The Atomic And Electronic Structures Of Polyperyleneimide: On The Origin Of Photocatalytic Oxygen Evolution Activity, Yi-Qing Wang, Zhi Lin, Ming-Tao Li, Shao-Hua Shen

Journal of Electrochemistry

Polymeric perylene diimide (PDI) has been evidenced as a good candidate for photocatalytic water oxidation, yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration. Herein, with crystal and atomic structures of the self-assembled PDI revealed from the X-ray diffraction pattern, the electronic structure is theoretically illustrated by the first-principles density functional theory calculations, suggesting the suitable band structure and the direct electronic transition for efficient photocatalytic oxygen evolution over PDI. It is confirmed that the carbonyl O atoms on the conjugation structure serve as the active sites for oxygen evolution reaction by the crystal …


Defect Characterization Of Sic Schottky Barrier Diode Using Deep Level Transient Spectroscopy, Zachary I. Mccoy May 2025

Defect Characterization Of Sic Schottky Barrier Diode Using Deep Level Transient Spectroscopy, Zachary I. Mccoy

Electrical Engineering and Computer Science Undergraduate Honors Theses

The aim of this project is to use deep level transient spectroscopy (DLTS) to energetically evaluate defects by using the carrier concentration dependence on temperature and where these carriers may experience deviation from standard predictions. These defects become apparent through multiple C-V measurements that are swept through a temperature range. By analyzing trends with respect to temperature, the defects can be energetically “located,” and thus identified. This identification can help streamline semiconductor material manufacturing/growth because DLTS identifies potential defect causes by providing data to characterize semiconductor mid-band defects. DLTS can assess nearly all parameters associated with traps/defects including density, thermal …


Signal Modeling Of High Purity Germanium Detectors, Brooke Parker Thibodeau May 2025

Signal Modeling Of High Purity Germanium Detectors, Brooke Parker Thibodeau

Honors Scholar Theses

Pulse shape analysis can be used to analyze radiation incident on a semiconductor diode detector. Finite element analysis (FEA) can be used to simulate high purity germanium detectors with user-specified geometry, impurity concentration, and bias voltage. Subsequent streamline calculation can be used to conduct pulse shape analysis for single and multiple site gamma-ray interactions within the detector volume. Cross sections of the detector can be visualized by contour plots of the electric field, drift velocity magnitude, and collection time, as well as t30 and t90 rise-time values.


The Evolution Of Nanoparticles In Nanoparticle Doped Optical Fibers, Mary Cahoon May 2025

The Evolution Of Nanoparticles In Nanoparticle Doped Optical Fibers, Mary Cahoon

All Dissertations

Optical fiber and fiber laser technologies based on silica glass are critical to many technologies today. One method to improve the optical performance of laser fibers is engineer the local environment around the active elements in the glass. To that end, this Dissertation focused on the fabrication and characterization of fibers made with nanoparticles incorporated into the glass to control the local composition. First, the nanoparticle composition and structure was analyzed as it evolved from from the initially-synthesized form to incorporation into the dense aluminum-silicate glass. The aluminum oxide in the glass was found to be important not only to …


Advanced Manufacturing Of Multifunctional Shape Memory Polymer Composites And Self-Healing Systems, John B. Konlan Apr 2025

Advanced Manufacturing Of Multifunctional Shape Memory Polymer Composites And Self-Healing Systems, John B. Konlan

LSU Doctoral Dissertations

The need for multifunctional light weight structures for engineering applications is on the rise. Multifunctional composites are desired because of their ability to combine multiple functionalities into one structure. The advantages of a high strength-to-weight ratio of multifunctional composites make them desirable and suitable for use in energy-efficient applications. Shape-memory polymers (SMPs) have attracted interest over the past several decades because of their multifunctional nature. They have found use in many applications such as aerospace, satellites, automobiles, textiles, and biomedical devices, where lightweight and multifunctionality are key. The self-healing nature of most SMPs makes them suitable for use in lightweight …


Sustainable Solutions To Eutrophication: The Role Of Glass Fertilizers, Lucas Greiner, Charmayne Lonergan Apr 2025

Sustainable Solutions To Eutrophication: The Role Of Glass Fertilizers, Lucas Greiner, Charmayne Lonergan

Miners Solving for Tomorrow Research Conference

No abstract provided.


Josephson Junctions: Fabrication And Applications For The Axion Dark Matter Experiment, Jonah M. Sachs Apr 2025

Josephson Junctions: Fabrication And Applications For The Axion Dark Matter Experiment, Jonah M. Sachs

Senior Honors Papers / Undergraduate Theses

The observation of axions could revolutionize the world of physics. Through microwave frequency cavity readout of the photons associated with these axions, the ADMX project at WashU utilizes multiple different forms of the Josephson junction (JJ), a superconductive circuit element. The physics behind the JJ are essential to understanding its operation for resonant cavity readout in addition to parametric amplification. Parametric amplifiers produced using JJs can approach the signal-to-noise ratio set by quantum mechanics, and prove essential for the amplification chain used by the ADMX experiment for axionic detection. The limits of these amplifiers are set by the noise tuning …


Synergy In Materials: Leveraging Phosphosilicate Waste Forms For Electrochemical Salt Waste, Jonathan S. Evarts, Brian J. Riley, Charmayne E. Lonergan, Michaella S. Harris, Jincheng Bai, Eric W. Bohannan, Iheanyichukwu Ajoku, Saehwa Chong, John S. Mccloy Mar 2025

Synergy In Materials: Leveraging Phosphosilicate Waste Forms For Electrochemical Salt Waste, Jonathan S. Evarts, Brian J. Riley, Charmayne E. Lonergan, Michaella S. Harris, Jincheng Bai, Eric W. Bohannan, Iheanyichukwu Ajoku, Saehwa Chong, John S. Mccloy

Materials Science and Engineering Faculty Research & Creative Works

Waste forms containing glassy and crystalline phosphate and silicate phases were produced to immobilize salt waste simulants from pyro processing and characterized by using Raman spectroscopy, Mössbauer spectroscopy, X-ray diffraction, scanning electron microscopy, heat capacity, and chemical durability measurements. In this work, a phosphosilicate waste form is presented to leverage the benefits of both borosilicate glasses and iron phosphate glasses. To improve waste loading, prior to immobilization, salt simulants were successfully dechlorinated using ammonium dihydrogen phosphate, mixed with a borosilicate frit (5–30 wt. %) and Fe2O3, and vitrified. Additions of 2.5–15 wt. % borosilicate glass (NBS3) improved normalized release rates …


Analysis Of An Ultra-Broadband Terahertz Metamaterial Absorber, Md Ariful Islam, Md Rezwan Ahmed, Oishi Jyoti, Pritu Sarkar, Md. Samiul Habib Mar 2025

Analysis Of An Ultra-Broadband Terahertz Metamaterial Absorber, Md Ariful Islam, Md Rezwan Ahmed, Oishi Jyoti, Pritu Sarkar, Md. Samiul Habib

Mechanical Engineering Faculty Publications

This paper introduces a metamaterial absorber (MA) based on vanadium dioxide (VO2) that achieves over 90% absorption of incident terahertz (THz) waves in between 4.50 THz to 11.90 THz with an average absorption of 94.64% and a relative absorption bandwidth (RAB) of 90.18% — the highest reported absorption bandwidth for VO2-based absorbers to our knowledge. The proposed metamaterial absorber features a design with a central square surrounded by four ’T’-shaped elements on each side, symmetrically arranged on a TOPAS dielectric substrate. We perform all numerical analyses keeping the phase-changing material VO2 in the metallic state, and our simulation results show …


Effect Of Niobium Dopant On Zno Thin Films Prepared Via The Sol–Gel Spin Coating Method, Kevin Alvin Eswar, Nur Fairuz Rostan, Maryam Mohamad, Rabiatuladawiyah Md Akhir, Rosfayanti Rasmidi, Muliyadi Guliling, Najwa Ezira Azhar, Irmaizatussyehdany Buniyamin, Mohd Firdaus Malek, Mohamad Rusop Mahmood, Husairi Fadzilah Suhaimi, Saifollah Abdullah Mar 2025

Effect Of Niobium Dopant On Zno Thin Films Prepared Via The Sol–Gel Spin Coating Method, Kevin Alvin Eswar, Nur Fairuz Rostan, Maryam Mohamad, Rabiatuladawiyah Md Akhir, Rosfayanti Rasmidi, Muliyadi Guliling, Najwa Ezira Azhar, Irmaizatussyehdany Buniyamin, Mohd Firdaus Malek, Mohamad Rusop Mahmood, Husairi Fadzilah Suhaimi, Saifollah Abdullah

Makara Journal of Science

Thin films of zinc oxide (ZnO) and niobium (Nb)-doped ZnO were deposited on a glass substrate using the sol–gel spin coating method. Diethanolamine, isopropyl alcohol, and zinc acetate served as the stabilizers, solvent, and starting ma-terial, respectively. Niobium pentachloride was employed as the dopant source. Energy-dispersive X-ray analysis con-firmed Nb incorporation. Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and ultravio-let–visible spectroscopy (UV–Vis) analyses characterized the morphology, structure, and optics of the films, respective-ly. Both films, comprising nanoparticles, were visible in FESEM. Nb doping reduced the particle size from 44.2 nm to 35.8 nm. The XRD peaks at 31.23°, …


Fabrication Of Microscale Oxide Architectures On Silicon Via A Cmos-Compatible, Deposition-Last Process, Jamal A. Brown Jan 2025

Fabrication Of Microscale Oxide Architectures On Silicon Via A Cmos-Compatible, Deposition-Last Process, Jamal A. Brown

Material Science and Engineering Theses - Archive

This work explores the feasibility of integrating complex oxide devices on silicon using a CMOS-compatible, deposition-last approach. While previous demonstrations of this method have succeeded at larger scales, this study focuses on extending the process to microscale features, with lateral dimensions as small as two microns. The fabrication sequence begins with photolithographic patterning and reactive ion etching of the silicon substrate, followed by the deposition of a silicon nitride mask to delineate device regions. We then epitaxially grew SrTiO3 and La-doped SrTiO3 layers on top of the nitride mask via molecular beam epitaxy. Electrical transport measurements of the La:STO layer …


A Fault-Tolerant Exchange-Coupled Spin-Ensemble Qubit At Elevated-Temperatures, Aniruddha Chakraborty Jan 2025

A Fault-Tolerant Exchange-Coupled Spin-Ensemble Qubit At Elevated-Temperatures, Aniruddha Chakraborty

Theses and Dissertations

This thesis introduces a novel qubit architecture: the ferromagnetic exchange-coupled spin ensemble qubit (E-qubit), designed to address the noise-induced instability. In this work, the time evolution of the ensemble’s density matrix is studied using the Liouville–von Neumann equation. To benchmark against a single-spin qubit, the gate fidelity of an E-qubit is computed in the presence of thermal noise. Coherence time is also analyzed under identical thermal condition and a linear scaling is observed with qubit size . The results show that, at 6 K , the gate fidelity error (0.7 % ) of the seven- spin ensemble is an order …