Article
Chemistry, Multidisciplinary
Junru Chen, Xiaojie Chen, Yanyan Liu, Yang Li, Juan Zhao, Zhiyong Yang, Yi Zhang, Zhenguo Chi
Summary: This study successfully reported a single-component luminescent molecule, 3-SPhF, with colorful emissions and investigated various luminescent mechanisms and characteristics in its crystal, expanding the understanding of the regularity of multiple emission centers in single-component compounds with dibenzofuran substituents.
Article
Chemistry, Physical
Xi Chen, Chunhua Li, Youming Xu, Andrei Dolocan, Gareth Seward, Ambroise Van Roekeghem, Fei Tian, Jie Xing, Shucheng Guo, Ni Ni, Zhifeng Ren, Jianshi Zhou, Natalio Mingo, David Broido, Li Shi
Summary: The study reveals the presence of various impurities in BAs, including Si, C, O, H, Te, Na, and I. Some of these impurities can act as shallow acceptors, leading to the p-type conducting behavior commonly measured in BAs. The thermal conductivity and hole mobility in the samples decrease with higher impurity concentrations.
CHEMISTRY OF MATERIALS
(2021)
Article
Multidisciplinary Sciences
Xiaokang Li, Yo Machida, Alaska Subedi, Zengwei Zhu, Liang Li, Kamran Behnia
Summary: We observe a thermal Hall conductivity with a large amplitude in a non-magnetic elemental insulator. The presence of this phenomenon in various insulators suggests a common mechanism, although the absolute amplitude varies greatly. The lack of correlation between the thermal Hall angle and the phonon mean-free-path imposes constraints on theoretical explanations.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Genrikh N. Gerasimov, Maria I. Ikim, Vladimir F. Gromov, Olusegun J. Ilegbusi, Leonid I. Trankhtenberg
Summary: The study demonstrates the formation of clusters with specific structure and sensory properties in SnO2-In2O3 composites by controlling the SnO2 concentration, and reveals the impact of different synthesis methods on the performance of the composites.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Physics, Applied
A. Frolov, A. P. Orlov, F. Gay, A. A. Sinchenko, P. Monceau
Summary: A comparative study of CDW sliding in NbSe3 at low temperatures was conducted, comparing two configurations. It was found that the threshold electric field for CDW depinning is sharp, measuring down to 0.1 mK. Below 4.2 K, the threshold electric field becomes temperature-independent, indicating a crossover from thermal fluctuations to a tunneling mechanism for CDW depinning.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Vladimir Bruevich, Leila Kasaei, Sylvie Rangan, Hussein Hijazi, Zhenyuan Zhang, Thomas Emge, Eva Y. Andrei, Robert A. Bartynski, Leonard C. Feldman, Vitaly Podzorov
Summary: The first experimental realization of intrinsic charge conduction in lead-halide perovskite field-effect transistors is reported. This is enabled by a new vapor-phase epitaxy technique, extensive materials analysis, and the fabrication of near-ideal FETs. The study reveals an increase in intrinsic mobility with decreasing temperature, indicating phonon-limited band transport.
ADVANCED MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Guoxin Zhuang, Qihui Fang, Jinxin Wei, Chengkai Yang, Muqing Chen, Zikun Lyu, Zanyong Zhuang, Yan Yu
Summary: By utilizing oriented etching of a metal-organic framework (MOF), highly ordered nanostructures can be designed successfully. The resulting nanostructures show enhanced efficiency in catalyzing visible-light-driven hydrogen evolution, indicating potential for advanced photocatalyst design.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Ning Rui, Xuelong Wang, Kaixi Deng, Jorge Moncada, Rina Rosales, Feng Zhang, Wenqian Xu, Iradwikanari Waluyo, Adrian Hunt, Eli Stavitski, Sanjaya D. Senanayake, Ping Liu, Jose A. Rodriguez
Summary: The use of an indium oxide (In2O3)-based catalyst in the hydrogenation of CO2 to methanol shows high selectivity and catalytic activity, significantly increasing the methanol yield. The dynamic nature of the RuO2/In2O3 catalyst structure under CO2 hydrogenation conditions leads to the formation of RuOx-In2O3-x interfacial sites, which promote selective methanol synthesis.
Article
Materials Science, Coatings & Films
Vyacheslav Vasyltsiv, Andriy Luchechko, Yaroslav Zhydachevskyy, Lyudmyla Kostyk, Roman Lys, Dmytro Slobodzyan, Rafal Jakiela, Bohdan Pavlyk, Andrzej Suchocki
Summary: The optical properties of beta-Ga2O3:Cr crystals can be significantly improved by annealing in oxygen atmosphere and codoping with magnesium, resulting in increased Cr3+ luminescence yield and resistivity changes.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2021)
Article
Multidisciplinary Sciences
Wenchao Wan, Yonggui Zhao, Shiqian Wei, Carlos A. Triana, Jingguo Li, Andrea Arcifa, Christopher S. Allen, Rui Cao, Greta R. Patzke
Summary: The authors reported the structural dynamics of dual-site nickel-iron single-atom oxygen electrocatalysts under reaction conditions, proposing a dual-site pathway for the water oxidation reaction. Single-atom catalysts with maximum metal utilization efficiency show great potential for sustainable catalytic applications and fundamental mechanistic studies. The convenient molecular tailoring strategy based on graphitic carbon nitride as support allows for the rational design of single-site and dual-site single-atom catalysts.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Panpan Li, Zhaoyu Jin, Zhiwei Fang, Guihua Yu
Summary: The necessity for sustainable ammonia production using economic and environment-friendly technologies is increasing globally. This study presents an iron-based single-atom catalyst with uniform atomic dispersion on carbon, which exhibits high NH3 yield rate and faradaic efficiency. The catalyst's high selectivity for NH3 is attributed to the unique electronic structures of the individual Fe sites.
ENERGY & ENVIRONMENTAL SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Subham Ranjan, Ryota Morioka, Meguya Ryu, Junko Morikawa, Satoshi Takamizawa
Summary: This study investigates the mechanical deformation in two cocrystals and reveals the relationship between structure and properties, providing guidance for the design of organic crystals with superelastic or ferroelastic properties based on rational selection of intermolecular interactions.
Article
Chemistry, Physical
Wenxin Liu, Jiabin Zou, Shuni Li, Jinkun Li, Feihu Li, Zili Zhan, Yeguang Zhang
Summary: A new bilayer design consisting of a Pd/In2O3 sensitive layer and an In2O3/Al2O3 catalytic filter layer is proposed to prevent the deactivation of hydrogen sensors. The In2O3/Al2O3 layer hinders the penetration of HMDSO and its decomposition products, leading to enhanced H2 response of the sensors. The bilayer sensors demonstrate high response (Ra/Rg = 53) and ultra-fast response time (1 s) towards 3000 ppm H2 at 365 degrees C, with almost unchanged resistance and H2 response after 40 min of 10 ppm HDMSO poisoning.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Bogdan Sawicki, Elzbieta Tomaszewicz, Tadeusz Gron, Monika Oboz, Joachim Kusz, Marek Berkowski
Summary: The single crystals of PNMWO with scheelite-type structure have been successfully grown by the Czochralski method. Research has shown that replacing diamagnetic Pb2+ ions with paramagnetic Nd3+ ones leads to significant effects of orbital diamagnetism and Van Vleck's paramagnetism, n-type electrical conductivity, and constant dielectric values.
Article
Chemistry, Physical
Diana Chaykina, Fahimeh Nafezarefi, Giorgio Colombi, Steffen Cornelius, Lars J. Bannenberg, Herman Schreuders, Bernard Dam
Summary: Thin films of rare earth metal oxyhydrides exhibit a photochromic effect, and the composition and encapsulation of the films can modify their band gap, crystal structure, photochromic contrast, and lifetime. The annealing process and defects are found to be crucial for the reversibility of the bleaching speed.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Engineering, Electrical & Electronic
Chao-Ching Chiang, Chan-Wen Chiu, Fan Ren, Cheng-Tse Tsai, Yu-Te Liao, Josephine F. Esquivel-Upshaw, Stephen J. Pearton
Summary: This study presents a SARS-CoV-2 virus detection mechanism using stored disposable strips. The accuracy of this sensing platform is comparable to PCR and provides results in less than 30 seconds. The disposable strips, biofunctionalized with SARS-CoV-2 antibodies, detect the virus in saliva samples, and the detected signals are amplified and displayed on an LCD screen. The system demonstrates the ability to show qualitative results within 30 seconds and quantitative concentrations in 5 minutes.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B
(2023)
Article
Engineering, Electrical & Electronic
Minghan Xian, Jenna L. Stephany, Chan-Wen Chiu, Chao-Ching Chiang, Fan Ren, Cheng-Tse Tsai, Siang-Sin Shan, Yu-Te Liao, Josephine F. Esquivel-Upshaw, Stephen J. Pearton
Summary: Oral squamous cell carcinoma is a common type of lip and oral cavity cancer, which requires early detection for improved survival rates. A modular biological sensor utilizing transistor-based technology has been developed for rapid and accurate point of care detection of the cancer, providing opportunities for quick clinical diagnosis.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B
(2023)
Article
Physics, Applied
Md Abu Jafar Rasel, Nahid Sultan Al-Mamun, Sergei Stepanoff, Aman Haque, Douglas E. Wolfe, Fan Ren, Stephen J. Pearton
Summary: In this work, we illustrate the rejuvenation of degraded Ti/4H-SiC Schottky barrier diodes at room temperature within seconds by utilizing high-energy electron interactions with defects. By applying high current density electrical pulsing with low frequency and duty cycle to suppress temperature rise, we successfully decrease defect concentration and improve device performance beyond the pristine condition. The ultrafast and room temperature process has the potential to rejuvenate electronic devices in high power and harsh environmental conditions.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Md Abu Jafar Rasel, Ryan Schoell, Nahid Sultan Al-Mamun, Khalid Hattar, C. Thomas Harris, Aman Haque, Douglas E. Wolfe, Fan Ren, Stephen J. Pearton
Summary: This study investigated the effects and mechanism of IL-37 on pyroptosis in RA-FLSs induced by TNF-a. It was found that IL-37 inhibited inflammation and reduced pyroptosis-related protein expression in RA-FLSs. The study also revealed that IL-37 alleviates TNF-a-induced pyroptosis in RA-FLSs by inhibiting NF-?B/GSDMD signaling.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Review
Materials Science, Multidisciplinary
Benjamin C. Letson, John W. Conklin, Peter Wass, Simon Barke, Guido Mueller, Md Abu Jafar Rasel, Aman Haque, Stephen J. Pearton, Fan Ren
Summary: There are various applications for deep UV AlGaN Light-Emitting Diodes (LEDs), including virus inactivation, air and water purification, sterilization, bioagent detection, and UV polymer curing. The long-term stability of these LEDs is important for space missions such as the Laser Interferometer Space Antenna (LISA). The literature review shows that the decline in output power of these LEDs over extended operating times is mainly driven by current and temperature, with the degradation rate dependent on the cube of drive current density and exponentially on temperature. The main mechanism for this decline is believed to be the creation/migration of point defects. Pre-screening based on the ratio of band edge-to-midgap emission and LED ideality factor can identify devices with long lifetimes (>10,000 h).
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2023)
Article
Crystallography
Jian-Sian Li, Hsiao-Hsuan Wan, Chao-Ching Chiang, Xinyi Xia, Timothy Jinsoo Yoo, Honggyu Kim, Fan Ren, Stephen J. Pearton
Summary: Vertical heterojunction rectifiers with p-type NiO and thick Ga2O3 drift layers grown on Sn-doped β-Ga2O3 substrates exhibited breakdown voltages > 8 kV. Low drift doping concentration, low power during NiO deposition, and the formation of a guard ring were key factors for achieving excellent performance. These results demonstrate the potential of NiO/Ga2O3 rectifiers beyond SiC and GaN.
Article
Engineering, Electrical & Electronic
Sergei P. Stepanoff, Aman Haque, Fan Ren, Stephen Pearton, Douglas E. Wolfe
Summary: The susceptibility of electronics to radiation increases as the size and complexity of electronic chips or systems increase. This study develops an indirect technique to identify radiation-susceptible regions and demonstrates its effectiveness in rapid detection.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B
(2023)
Article
Chemistry, Physical
Chao-Ching Chiang, Xinyi Xia, Jian-Sian Li, Fan Ren, S. J. Pearton
Summary: The 8-polytype of Ga2O3 is a promising material for next generation power electronics and solar-blind UV photodetectors due to its high critical electric field strength and ability to be grown as large diameter single crystals. Dry etching is being focused on for patterning such devices, but it may cause surface modification and damage to the material. This study demonstrates that dry etch damage in 8-Ga2O3 leads to a reduction in near-surface carrier concentration, affecting device parameters like on-state resistance and introducing trap-assisted space-charge-limited conduction in the damaged layers.
APPLIED SURFACE SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Jian-Sian Li, Xinyi Xia, Chao-Ching Chiang, Hsiao-Hsuan Wan, Fan Ren, Jihyun Kim, S. J. Pearton
Summary: Neutrons generated by charge-exchange reactions were used to irradiate Schottky Ga2O3 rectifiers and NiO/Ga2O3 p-n heterojunction rectifiers. The breakdown voltage was improved for Schottky rectifiers but highly degraded for their NiO/Ga2O3 counterparts. The switching characteristics were degraded for both types of devices after irradiation.
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Jian-Sian Li, Chao-Ching Chiang, Xinyi Xia, Hsiao-Hsuan Wan, Fan Ren, S. J. Pearton
Summary: Large area vertical NiO/β n-Ga2O/n(+) Ga2O3 heterojunction rectifiers with high breakdown voltage (3.6 kV) and large conducting currents (4.8 A) are demonstrated. The performance exceeds the unipolar 1D limit for GaN, indicating the potential of β-Ga2O3 for future high-power rectification devices. The breakdown voltage is strongly dependent on the carrier concentration in the drift region.
ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY
(2023)
Article
Crystallography
Jian-Sian Li, Hsiao-Hsuan Wan, Chao-Ching Chiang, Fan Ren, Stephen J. Pearton
Summary: The stability of vertical geometry NiO/Ga2O3 rectifiers was examined under two types of annealing. It was found that annealing at 300 degrees C resulted in the best performance, including maximizing breakdown voltage and on-off ratio, lowering forward turn-on voltage, reducing reverse leakage current, and maintaining on resistance. The surface morphology remained smooth and the NiO exhibited a bandgap of 3.84 eV with an almost unity Ni2O3/NiO composition.
Article
Crystallography
Chao-Ching Chiang, Jian-Sian Li, Hsiao-Hsuan Wan, Fan Ren, Stephen J. Pearton
Summary: Ga2O3 heterojunction rectifiers with NiO as the solution on the p-type side have become a novel candidate for power conversion applications. In this study, the optimized design of high-breakdown NiO/Ga2O3 rectifiers was examined using the Silvaco TCAD simulator to determine the electric field distribution. The doping concentration, guard ring thickness, and extension beyond the anode were all important factors in determining the breakdown location. The transition phenomenon from the edge of the NiO extension to the top contact periphery was found to be correlated with the depletion effect.
Article
Materials Science, Multidisciplinary
Jian-Sian Li, Chao-Ching Chiang, Xinyi Xia, Hsiao-Hsuan Wan, Fan Ren, S. J. Pearton
Summary: NiO/β-Ga2O3 vertical rectifiers show near-temperature-independent breakdown voltages (V-B) of >8 kV at 600 K. The power figure of merit (V-B)²/R-ON for 100 μm diameter devices is 9.1 GW cm(-2) at 300 K and 3.9 GW cm(-2) at 600 K. In contrast, Schottky rectifiers on the same wafers have V-B of about 1100 V at 300 K with a negative temperature coefficient of breakdown. The power figure of merit for Schottky rectifiers is much lower compared to the heterojunction rectifiers. The results demonstrate the potential of using transparent oxide heterojunctions for high temperature, high voltage applications.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Review
Engineering, Electrical & Electronic
S. J. Pearton, Xinyi Xia, Fan Ren, Md Abu Jafar Rasel, Sergei Stepanoff, Nahid Al-Mamun, Aman Haque, Douglas E. Wolfe
Summary: Wide bandgap semiconductors SiC and GaN are used in power electronics and light-emitting diodes. They have higher radiation hardness compared to Si devices due to larger threshold energies for creating defects and high rates of defect recombination. However, heavy-ion-induced catastrophic burnout commonly occurs in SiC and GaN power devices. Light-emitting devices are not affected by this mechanism. Strain has also been identified as a parameter affecting radiation susceptibility of wide bandgap devices.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B
(2023)
Article
Engineering, Electrical & Electronic
Chao-Ching Chiang, Hsiao-Hsuan Wan, Jian-Sian Li, Fan Ren, Timothy Jinsoo Yoo, Honggyu Kim, S. J. Pearton
Summary: Sputtered p-NiO films were used to suppress gate leakage and produce a positive shift in the gate voltage of AlGaN/GaN high-electron mobility transistors for e-mode operation. The utility of NiO gates in increasing the on-off ratio and shifting the threshold voltage in comparison to Schottky gates was demonstrated.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B
(2023)
