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Reliable operation of Cr2O3:Mg/β-Ga2O3 p-n heterojunction diodes at 600◦C

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arXiv

arXiv 2024年

作者： Callahan, William A. Egbo, Kingsley Lee, Cheng-Wei Ginley, David O'Hayre, Ryan Zakutayev, Andriy Materials Science Center National Renewable Energy Laboratory GoldenCO80401 United States Advanced Energy Systems Graduate Program Colorado School of Mines GoldenCO80401 United States Department of Metallurgical and Materials Engineering Colorado School of Mines GoldenCO80401 United States

β-Ga2O3-based semiconductor heterojunctions have recently demonstrated improved performance at high voltages and elevated temperatures and are thus promising for applications in power electronic devices and harsh-environment sensors. However, the long-term reliability of these ultra-wide band gap (UWBG) semiconductor devices remains barely addressed and may be strongly influenced by chemical reactions at the p-n heterojunction interface. Here, we experimentally demonstrate operation and evaluate the reliability of Cr2O3:Mg/β-Ga2O3 p-n heterojunction diodes at during extended operation at 600◦C, as well as after 30 repeated cycles between 25-550◦C. The calculated pO3-temperature phase stability diagram of the Ga-Cr-O material system predicts that Ga2O3 and Cr2O3 should remain thermodynamically stable in contact with each other over a wide range of oxygen pressures and operating temperatures. The fabricated Cr2O3:Mg/β-Ga2O3 p-n heterojunction diodes show room-temperature on/off ratios >104 at ±5V and a breakdown voltage (VBr) of -390V. The leakage current increases with increasing temperature up to 600◦C, which is attributed to Poole-Frenkel emission with a trap barrier height of 0.19 eV. Over the course of a 140-hour thermal soak at 600◦C, both the device turn-on voltage and on-state resistance increase from 1.08V and 5.34 mΩ-cm2 to 1.59V and 7.1 mΩ-cm2 respectively. This increase is attributed to the accumulation of Mg and MgO at the Cr2O3/Ga2O3 interface as observed from TOF-SIMS analysis. These findings inform future design strategies of UWBG semiconductor devices for harsh environment operation and underscore the need for further reliability assessments for β-Ga2O3 based devices. © 2024, CC BY.

关键词： Gallium compounds

Effect of Heat Treatment on Improving Oer Activity of Nifeooh Based Aerogels: A Combined Experimental and Theoretical Study

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SSRN 2024年

作者： Lakhanlal Rimon, Or Moschkowitsch, Wenjamin Elbaz, Lior Toroker, Maytal Caspary Department of Materials Science and Engineering Technion-Israel Institute of Technology Haifa3200003 Israel Bar Ilan University Ramat-Gan52900 Israel The Nancy and Stephen Grand Technion Energy Program Technion - Israel Institute of Technology Haifa3200003 Israel

Enhanced catalytic activity of oxygen evolution reaction (OER) catalysts can make water electrolysis more efficient. This study focuses on the use of a simple strategy of heat treatment to enhance the catalytic activity of NiFeOOH-based aerogels. The study shows that heat treatment of this aerogel at 150 °C leads to significant improvement in its catalytic activity, as evident in the staircase voltammetry results. To understand how heat treatment improves the catalytic activity, a DFT+U calculation was carried out on heat-treated and non-heat treated catalysts. The calculation shows that the overpotential for OER decreases with heat treatment, which is related to the relative stability of the intermediates in heat-treated and non-heat treated catalysts. Also, it has been found that heat treatment decreases work function, which might improve charge transfer and, thus, catalytic activity. Our calculations are in line with the experimental results that demonstrate the potential of controlling water content on catalytic efficiency. © 2024, The Authors. All rights reserved.

关键词： Heat treatment

Two-dimensional materials for future information technology: status and prospects

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science China(Information sciences) 2024年第6期67卷 1-147页

作者： Hao QIU Zhihao YU Tiange ZHAO Qi ZHANG Mingsheng XU Peifeng LI Taotao LI Wenzhong BAO Yang CHAI Shula CHEN Yiqi CHEN Hui-Ming CHENG Daoxin DAI Zengfeng DI Zhuo DONG Xidong DUAN Yuhan FENG Yu FU Jingshu GUO Pengwen GUO Yue HAO Jun HE Xiao HE Jingyi HU Weida HU Zehua HU Xinyue HUANG Ziyang HUANG Ali IMRAN Ziqiang KONG Jia LI Qian LI Weisheng LI Lei LIAO Bilu LIU Can LIU Chunsen LIU Guanyu LIU Kaihui LIU Liwei LIU Sheng LIU Yuan LIU Donglin LU Likuan MA Feng MIAO Zhenhua NI Jing NING Anlian PAN Tian-Ling REN Haowen SHU Litao SUN Yue SUN Quanyang TAO Zi-Ao TIAN Dong WANG Hao WANG Haomin WANG Jialong WANG Junyong WANG Wenhui WANG Xingjun WANG Yeliang WANG Yuwei WANG Zhenyu WANG Yao WE... Department of Applied Physics The Hong Kong Polytechnic University Key Laboratory for Micro-Nano Physics and Technology of Hunan Province College of Materials Science and EngineeringHunan University College of Integrated Circuits Zhejiang University Shenzhen Geim Graphene Center Shenzhen Key Laboratory of Layered Materials for Value-Added ApplicationsTsinghua-Berkeley Shenzhen Institute & Institute of Materials ResearchTsinghua Shenzhen International Graduate SchoolTsinghua University State Key Laboratory of Extreme Photonics and Instrumentation College of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZijingang CampusZhejiang University National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences CAS Key Laboratory of Nanophotonic Materials and Devices & Key Laboratory of Nanodevices and Applications i-LabSuzhou Institute of Nano-Tech and Nano-Bionics (SINANO)Chinese Academy of Sciences College of Chemistry and Chemical Engineering Hunan University Key Laboratory of Quantum State Construction and Manipulation (Ministry of Education) Department of PhysicsRenmin University of China School of Integrated Circuits Beijing National Research Center for Information Science and Technology (BNRist)Tsinghua University School of Electronic Science and Engineering Nanjing University The State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology Shaanxi Joint Key Laboratory of GrapheneSchool of MicroelectronicsXidian University Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education School of Physics and TechnologyWuhan University School of Integrated Circuits Huazhong University of Science and Technology Center for Nanochemistry (CNC) Beijing Science and Engineering Center for NanocarbonsBeijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking University State Key Laboratory for Artificial Microstruct

Over the past 70 years, the semiconductor industry has undergone transformative changes,largely driven by the miniaturization of devices and the integration of innovative structures and materials. Two-dimensional(2D) materials like transition metal dichalcogenides(TMDs) and graphene are pivotal in overcoming the limitations of silicon-based technologies, offering innovative approaches in transistor design and functionality, enabling atomic-thin channel transistors and monolithic 3D integration. We review the important progress in the application of 2D materials in future information technology, focusing in particular on microelectronics and optoelectronics. We comprehensively summarize the key advancements across material production, characterization metrology, electronic devices, optoelectronic devices, and heterogeneous integration on silicon. A strategic roadmap and key challenges for the transition of 2D materials from basic research to industrial development are outlined. To facilitate such a transition, key technologies and tools dedicated to 2D materials must be developed to meet industrial standards, and the employment of AI in material growth, characterizations, and circuit design will be essential. It is time for academia to actively engage with industry to drive the next 10 years of 2D material research.

关键词： two-dimensional (2D) materials information technology production technology standardization of characterization microelectronic devices optoelectronic devices multi-functional integration

Ab initio phonon transport across grain boundaries in graphene using machine learning based on small dataset

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Physical Review materials 2022年第4期6卷 044004-044004页

作者： Amirreza Hashemi Ruiqiang Guo Keivan Esfarjani Sangyeop Lee Computational Modeling and Simulation Program University of Pittsburgh Pittsburgh Pennsylvania 15261 USA Department of Mechanical Engineering and Materials Science University of Pittsburgh Pittsburgh Pennsylvania 15261 USA Department of Mechanical and Aerospace Engineering University of Virginia Charlottesville Virginia 22904 USA Department of Materials Science and Engineering University of Virginia Charlottesville Virginia 22904 USA Department of Physics University of Virginia Charlottesville Virginia 22904 USA Department of Physics and Astronomy University of Pittsburgh Pittsburgh Pennsylvania 15261 USA

Establishing the structure-property relationship for grain boundaries (GBs) is critical for developing next-generation functional materials but has been severely hampered due to its extremely large configurational space. Atomistic simulations with low computational cost and high predictive power are strongly desirable, but the conventional simulations using empirical interatomic potentials and density functional theory suffer from the lack of predictive power and high computational cost, respectively. A machine learning interatomic potential (MLIP) recently emerged but often requires extensive size of the training dataset, making it a less feasible approach. Here, we demonstrate that an MLIP trained with a rationally designed small training dataset can predict thermal transport across GBs in graphene with ab initio accuracy at an affordable computational cost. We employed a rational approach based on the structural unit model to find a small set of GBs that can represent the entire configurational space and thus can serve as a cost-effective training dataset for the MLIP. Only 5 GBs were found to be enough to represent the entire configurational space of graphene GBs. Using the atomistic Green's function approach and the MLIP, we revealed that the structure-thermal resistance relation in graphene does not follow the common understanding that large dislocation density causes larger thermal resistance. In fact, thermal resistance is nearly independent of dislocation density at room temperature and is higher when the dislocation density is small at sub-room temperature. We explain this intriguing behavior with the buckling near a GB causing a strong scattering of flexural phonon modes. In this paper, we show that a machine learning technique combined with conventional wisdom (e.g., structural unit model) can extend the recent success of ab initio thermal transport simulation, which has been mostly limited to single crystals, to complex yet practically important polycry

关键词： Phonons Graphene Landauer formula Machine learning

MnO2-directed synthesis of NiFe-LDH@FeOOH nanosheeet arrays for supercapacitor negative electrode

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Chinese Chemical Letters 2020年第9期31卷 2343-2346页

作者： Qing Sun Kexin Yao Yuxin Zhang Multi-scale Porous Materials Center Institute of Advanced Interdisciplinary StudiesCollege of Chemistry and Chemical EngineeringChongqing UniversityChongqing 400044China State Key Laboratory of Mechanical Transmission College of Materials Science and EngineeringChongqing UniversityChongqing 400044China

The complex-architectured NiFe-LDH@FeOOH negative material was first prepared by simple two-step hydrothermal *** this study,the porous nanostructure of FeOOH nanosheets features a large number of accessible channels to electroactive sites and the two-dimensional layered structure of NiFe-LDH nanosheets have an open spatial structure with high specific surface area,which enhance the diffusion of ions in the active *** from above advantages,the excellent electrochemical properties were ***-LDH@FeOOH nanocomposites present high specific capacitance(1195 F/g at a current density of 1 A/g),lower resistance and well cycling performance(90.36% retention after 1000 cycles).Furthermore,the NiFe-LDH@MnO2//NiFe-LDH@FeOOH supercapacitor exhibits22.68 Wh/kg energy density at 750 W/kg power density,demonstrating potential application in energy storage devices.

关键词： NiFeLDH FeOOH Supercapacitor Negative electrode Electrochemical performance

Terahertz Emission Improvement of Gallium-Arsenide-Based Bowtie Photoconductive Antenna by Aao-Patterned Gold Nanoparticles Integration on the Photoconducting Gap

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SSRN 2024年

作者： Dela Rosa, Lourdes Nicole Alaba, Kenneth Jay Cabello, Neil Irvin Loberternos, Regine Ferrolino, John Paul Verona, Ivan Cedrick Juguilon, Vince Paul Salvador, Arnel Somintac, Armando Kitahara, Hideaki De Los Reyes, Alexander Bardolaza, Hannah Tani, Masahiko Estacio, Elmer National Institute of Physics University of the Philippines Diliman Metro Manila Quezon City Philippines Laser Science Laboratory Toyota Technological Institute Nagoya Japan Materials Science Engineering Program University of the Philippines Diliman Metro Manila Quezon City Philippines Research Center for Development of Far-Infrared Region University of Fukui Fukui Japan

We report on the terahertz emission improvement in GaAs-based photoconductive antennas (PCA) with gold (Au) nanoparticles (NPs) on the PCA gap, patterned using anodic aluminum oxide template. Two PCA devices were fabricated with Au NPs having average diameters of 200 nm and 20 nm. The THz peak-to-peak intensity increased ~2-fold for the 200-nm PCA, and increased ~1.5-fold in peak-to-peak intensity for the 20-nm PCA. Finite difference time domain (FDTD) simulations revealed that surface plasmon resonance enhancement effects were more pronounced for the 200-nm diameter Au NP PCA. The results demonstrate a cost-effective method of utilizing nanostructures to improve PCA performance. © 2024, The Authors. All rights reserved.

关键词： Gold nanoparticles

Halide Double Perovskite-Based Efficient Mechanical Energy Harvester and Storage Devices for Self-Charging Power Unit

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SSRN 2022年

作者： Yoon, Soon-Gil Ippili, Swathi Kim, Jong Heon Jella, Venkatraju Behera, Subhashree Vuong, Van-Hoang Jung, Jang-Su Cho, Yujang Ahn, Jaewan Kim, Il-Doo Chang, Yun Hee Kim, Hyun-Suk Department of Materials Science and Engineering Chungnam National University 99 Daehak-ro Yuseong-gu Daejeon34134 Korea Republic of Texas Materials Institute and Materials Science and Engineering Program The University of Texas AustinTX78712 United States 291 Daehak-ro Yuseong-gu Daejeon34141 Korea Republic of

With the rapid development of portable/wearable electronic devices, high-efficient and sustainable self-powered systems have considerably risen in demand to support their off-grid operation. Recently, metal halide perovskites (MHPs) have been suggested as promising materials for energy harvesting and storage devices because of their excellent optoelectronic, ferro/piezoelectric, and ion migration properties. However, the high toxicity and poor physicochemical stability of MHPs obstruct their practical application. Herein, for the first time, the potential of methylammonium tin halide (MA2SnX6;X = Cl, Br, and I) double perovskite thin films for high-efficient self-charging power units (SPUs) is elucidated by virtue of their high stability in air. To this end, the integration of a MA2SnCl6-based piezoelectric nanogenerator (PENG) with a lithium metal battery (LMB) which also uses the MA2SnCl6-based thin film as the cathode is demonstrated. The MA2SnCl6-based PENG exhibited a high output power density of 7.33 μW cm-2 and an excellent mechanical durability. Further, the MA2SnCl6 as a cathode in LMB recorded the highest specific capacity of 589.98 mAh g-1. Moreover, 1 nm-thick Al2O3 coating on the MA2SnCl6 surface improved the capacity retention from 16.9% to 75.1% for 100 cycles, indicating its stable performance. Further, the MA2SnCl6-based LMB is charged by the MA2SnCl6-based PENG and utilized as SPU for operating various small-scale electronics (humidity meter, calculator, and LED). This work, not only demonstrates the immediate feasibility of MHPs toward high-capacity batteries and energy harvesters, but also provides an insight into the general design principles of MHP-based devices. © 2022, The Authors. All rights reserved.

关键词： Cathodes

Facile synthesis of metal-polyphenol-formaldehyde coordination polymer colloidal nanoparticles with sub-50 nm for T_(1)-weighted magnetic resonance imaging

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Chinese Chemical Letters 2021年第2期32卷 842-848页

作者： Jing Qin Guohai Liang Bingxi Feng Gen Wang Na Wu Yonghui Deng Ahmed AElzatahry Abdulaziz Alghamdi Yongxi Zhao Jing Wei The Key Laboratory of Biomedical Information Engineering of Ministry of Education School of Life Science and TechnologyXi'an Jiaotong UniversityXi'an 710049China College of Biophotonics South China Normal UniversityGuangzhou 510631China Department of Chemistry Fudan UniversityShanghai 200433China Materials Science and Technology Program College of Arts and SciencesQatar UniversityPO Box 2713DohaQatar Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

Plant polyphenol-based coordination polymers(CPs) with ultra-small particle size and tailorable compositions are highly desired in biomedical applicatio ns,but their synthesis is still challenging due to the sophisticated coordination assembly process and unavoidable self-oxidation polymerization of polyphenol. He rein,a general ligand covalent-modification mediated coordination assembly strategy is proposed for the synthesis of water-dispersible CPs with tunable metal species(e.g., Gd,Cu,Ni,Zn,Fe)and ultra-small diameter(8.6-37.8 nm) using nontoxic plant polyphenol(e.g..tannic acid,gallic acid) as a polymerizable *** molecules react with formaldehyde firstly,which can effectively retard the oxidation induced self-polymerization of polyphenol and lead to the formation of metal ions containing CPs colloidal *** ultrafine nanoparticles with stably chelated metal io ns are highly water dispersible and thus advantageous for *** an example,ultra-small Gd contained CPs exhibit higher longitudinal relaxivity(r_(1)=25.5 L mmol^(-1) s^(-1)) value with low r2/r1(1.19) than clinically used Magnevist(Gd-DTPA,r1=3.7 L mmol^(-1) s^(-1)) .Due to the enhanced permeability and retention effect,they can be further used as a positive contrast agent for T1-weighted MR imaging of tumour.

关键词： Coordination polymer Nanoparticle Self-assembly Plant polyphenol Contrast agent

Thermodynamics of the Solid-Liquid Phase Equilibrium of a Binary System: Effect of a Chemical Reaction in the Liquid and Epitaxial Strain in the Solid

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SSRN 2023年

作者： Deymier, Alix C. Deymier, Pierre Alix Muralidharan, Krishna Latypov, Marat I. Department of Biomedical Engineering UConn Health FarmingtonCT06030 United States Department of Materials Science and Engineering University of Arizona TucsonAZ85721 United States Graduate Interdisciplinary Program in Applied Mathematics University of Arizona TucsonAZ85721 United States

We introduce two thermodynamics models of solid-liquid phase equilibrium of a binary system in the presence of (a) a chemical reaction in the liquid involving only one of the binary components and, (b) strain-inducing epitaxial conditions on the solid in addition to the chemical reaction in the liquid. These models show the existence of the counter intuitive behavior that epitaxy may promote recrystallization of the solid in spite of the reaction driving dissolution. The conditions for this recrystallization behavior are determined by the value of the epitaxial lattice matching composition, the temperature and the overall composition of the binary solid-liquid system. © 2023, The Authors. All rights reserved.

关键词： Chemical reactions