Article
Chemistry, Physical
Ning Zhang, Yongsheng Wang, Zihao Chen, Bin Zhou, Jie Gao, Yanxia Wu, Yong Ma, Hongjun Hei, Shengwang Yu
Summary: The quality of β-Ga2O3 films with top layer doping of nitrogen was found to be related to the N content and annealing atmosphere, leading to high transmittance and ultraviolet emission properties.
APPLIED SURFACE SCIENCE
(2022)
Article
Crystallography
Minglei Tang, Guodong Wang, Songhao Wu, Yang Xiang
Summary: Ultra-long Si-doped beta-Ga2O3 nanowires were prepared on annealed Al2O3-film/Si substrate by low-pressure chemical vapor deposition (LPCVD) with Au as catalyst. The nanowires have a length over 300 μm and diameters ranging from about 30 nm to about 100 nm in one-dimensional structures. Their crystal quality is good with (201) orientation confirmed by transmission electron microscopy and X-ray diffraction analysis. The nanowires exhibit three obvious blue luminescence peaks and good conductivity. A metal-semiconductor-metal device made with Ti/Au electrode shows a device current of 200 pA at a bias voltage of 3 V. The results demonstrate the direct growth of ultra-long Si-doped beta-Ga2O3 nanowires on Al2O3-film/Si substrates, which have a high length-diameter ratio and good electrical properties. A possible Si doping mechanism is also proposed.
Article
Chemistry, Physical
Yangyang Gao, Zhourui Xu, Xusheng Tian, Qian Feng, Xiaoli Lu, Chunfu Zhang, Jincheng Zhang, Yue Hao
Summary: The study focused on tin-assisted pure phase n-type ZrO2-doped epsilon-Ga2O3 films grown on epi-GaN/sapphire substrates using pulsed laser deposition. The thin films were characterized for their crystal structure and electrical properties, with a Schottky barrier diode exhibiting high rectification ratio and breakdown voltage. Interface states density and trap energy levels were also analyzed, showing promising results for potential applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Optics
Manuel Alonso-Orts, Gerwin Chilla, Rudolfo Hoetzel, Emilio Nogales, Jose M. San Juan, Maria L. No, Martin Eickhoff, Bianchi Mendez
Summary: This study reports optical confinement in the near-ultraviolet (near-UV) range in Ga2O3 nanowires (NWs) by distributed Bragg reflector (DBR) nanopatterned cavities. High-contrast DBRs act as end mirrors of cavities, designed and fabricated by focused ion beam etching. Experiment and simulations show good agreement in analyzing resonant modes of the cavities.
Article
Materials Science, Multidisciplinary
Naiji Zhang, Haoyue Liu, Qinglin Sai, Chongyun Shao, Changtai Xia, Lingyu Wan, Zhe Chuan Feng, H. F. Mohamed
Summary: The intentional incorporation of Fe impurities into beta-Ga2O3 crystals as capture traps significantly influences the structural, optical, and electronic properties of the material. Through annealing treatment, improvements in crystalline quality and reductions in conductivity were observed, showcasing the potential for high-performance applications.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Materials Science, Ceramics
Wei Chen, Teng Jiao, Zeming Li, Zhaoti Diao, Zhengda Li, Xin Dong, Yuantao Zhang, Baolin Zhang
Summary: The study prepared beta-Ga2O3 nanostructures in 1D nanowires and bulk films by thermal oxidation of GaAs substrate. The growth mechanisms were discussed and the NW films showed higher emission performance, with a successful fabrication of a p-GaAs/beta-Ga2O3 NWs heterojunction.
CERAMICS INTERNATIONAL
(2022)
Article
Physics, Multidisciplinary
J. Jesenovec, C. Pansegrau, M. D. McCluskey, J. S. McCloy, T. D. Gustafson, L. E. Halliburton, J. B. Varley
Summary: This study finds that exposure of Cu-doped beta-Ga2O3 to UV light (>4 eV) causes large, persistent photo induced darkening at room temperature. Light exposure converts Cu2+ to Cu3+ and leads to the appearance of O-H vibrational modes. Cu acceptors can form favorable complexes with hydrogen donors, and when these complexes absorb light, hydrogen is released, resulting in the formation of Cu3+ species and O-H modes.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Lei Shangguan, Long-Bing He, Sheng-Pan Dong, Yu-Tian Gao, Qian Sun, Jiong-Hao Zhu, Hua Hong, Chao Zhu, Zai-Xing Yang, Li-Tao Sun
Summary: In this paper, a facile method for fabricating β-Ga2O3 nanotubes using GaSb nanowires as sacrificial templates is reported. The length, diameter, and thickness of the nanotubes can be customized by using different GaSb nanowires and heating parameters. It is found that the Kirkendall effect and the sublimation process play critical roles in the transformation dynamics of the β-Ga2O3 nanotubes. The obtained β-Ga2O3 nanotubes exhibit promising photoelectric properties with high photoresponsivity and detectivity.
Article
Physics, Applied
Sudipto Saha, Lingyu Meng, A. F. M. Anhar Uddin Bhuiyan, Ankit Sharma, Chinmoy Nath Saha, Hongping Zhao, Uttam Singisetti
Summary: This study presents a novel approach for growing current blocking layers for vertical gallium oxide devices and characterizes their performance through electrical tests and simulations. The results demonstrate that the current blocking layers exhibit good blocking characteristics and optimized performance.
APPLIED PHYSICS LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Suman Bhandari, John L. Lyons, Darshana Wickramaratne, M. E. Zvanut
Summary: This work investigates the optical transitions of Mg-doped gallium oxide using photoinduced electron paramagnetic resonance spectroscopy. The data analysis reveals that the observed transition involves electron transition from the valence band to the defect and the energy level of Mg-Ga(-/0) is located 1.2 eV above the valence band maximum.
Article
Physics, Applied
Miaomiao Zhang, Shuai Kang, Liang Wang, Kun Zhang, Yutong Wu, Shuanglong Feng, Wenqiang Lu
Summary: A Ga2O3 nanowire network structure was successfully obtained on a sapphire substrate using chemical vapor deposition method, showing potential for high-performance solar-blind UV photodetectors.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Hui Zeng, Meng Wu, Haixia Gao, Yuansheng Wang, Hongfei Xu, Meijuan Cheng, Qiubao Lin
Summary: This paper investigates the influence of iron doping on beta-Ga2O3 material using first-principles calculations. The results show that iron preferentially incorporates into the octahedrally coordinated gallium site and forms V-Ga and O-i defects under oxygen-rich conditions. Furthermore, the complexes FeGaGai and FeGaVGa can significantly enhance the optical absorption in the visible-infrared region of the beta-Ga2O3 material.
Article
Physics, Applied
Anil Kumar Rajapitamahuni, Laxman Raju Thoutam, Praneeth Ranga, Sriram Krishnamoorthy, Bharat Jalan
Summary: By using high-field magnetotransport measurements, this study investigates donor state energy characteristics in Si-doped β-Ga2O3 films, revealing critical insights into impurity band conduction and defect energy levels in the material.
APPLIED PHYSICS LETTERS
(2021)
Article
Nanoscience & Nanotechnology
Subhajit Ghosh, Dinusha Herath Mudiyanselage, Fariborz Kargar, Yuji Zhao, Houqiang Fu, Alexander A. Balandin
Summary: This study investigates the temperature dependence of low-frequency electronic noise in NiOx/beta-Ga2O3 p-n heterojunction diodes. The results show that the noise spectral density follows a 1/f-type behavior at room temperature, but exhibits Lorentzian components at higher temperatures and current levels. Interestingly, the noise shows a non-monotonic dependence on temperature near T = 380 K. Raman spectroscopy reveals material changes above this temperature, leading to reduced noise. The normalized noise spectral density of these diodes is determined to be on the order of 10(-14) cm(2) Hz(-1) (f = 10 Hz) at 0.1 A cm(-2) current density. In terms of noise level, NiOx/beta-Ga2O3 p-n diodes perform excellently for new technology and occupy an intermediate position among devices with different ultra-wide-bandgap semiconductors. These findings contribute to the understanding of the electronic properties of NiOx/beta-Ga2O3 heterojunctions and promote the development of noise spectroscopy as a quality assessment tool for new electronic materials and device technologies.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Xiangyu Wang, Hengyang Qiao, Tong Liu, Fuzhou Song, Zhongfen An, Yue Xu, Lingcui Zhang, Feng Shi
Summary: Monoclinic beta-Ga2O3 samples with high crystallinity were prepared using the hydrothermal method. The presence of nanopores on the sample surfaces, formed by the dehydroxylation of the GaOOH precursor during the calcination process, was observed. Various vibrational modes of GaO bonds were identified in the Raman spectrum of beta-Ga2O3 samples. The photoluminescent spectrum showed the recombination of defects, including oxygen vacancy donors and gallium vacancy or gallium-oxygen vacancy acceptors.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2022)
Article
Chemistry, Multidisciplinary
Yujie Ma, Xiaoyan Liu, Xindong Wei, Jiamei Le, Yi Fu, Qiuqin Han, Houlin Ji, Zhi Yang, Hailong Wu
Summary: In this study, a series of yolk-shelled Au@Cu2O composites were synthesized using Au NPs, Au NRs, and Au NBPs for the first time. The yolk-shelled composites showed significantly higher photocatalytic activity compared to solid-shelled ones and pure Cu2O. Notably, yolk-shelled Au NR@Cu2O and Au NBP@Cu2O composites exhibited excellent near-infrared light-driven photocatalytic activity, which was not achievable with Au NP@Cu2O and pure Cu2O.
Article
Nanoscience & Nanotechnology
Feng Shao, Hong Li, Lu Yao, Shiwei Xu, Gang Li, Bin Li, Cheng Zou, Zhi Yang, Yanjie Su, Nantao Hu, Yafei Zhang
Summary: In this study, a flexible graphene-fiber-fabric-based three-dimensional conductive network was designed to create a binder-free and self-standing silicon anode, demonstrating excellent battery performance. The GFF/Si-37.5% and GFF/Si-29.1% electrodes exhibited outstanding performance in terms of cyclability and reversible capacity.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Huan Yin, Luoxi Zhang, Mingkui Zhu, Yue Chen, Tian Tian, Yafei Zhang, Nantao Hu, Zhi Yang, Yanjie Su
Summary: A novel method for improving the performance of SWCNT-based photodetectors through interfacial charge transfer induced by Au nanoparticle surface doping is reported. Experimental results show that AuNP doping can effectively enhance the generation and transport of photogenerated carriers, thereby significantly improving the performance of the photodetector. This study provides a simple route for enhancing the performance of SWCNT-based photodetectors and offers a new method for characterizing the interfacial charge transfer between dopants and SWCNTs.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Nanoscience & Nanotechnology
Peiyao Wang, Feng Shao, Bin Li, Yanjie Su, Zhi Yang, Nantao Hu, Yafei Zhang
Summary: In order to increase the specific capacitance of supercapacitors, polyaniline (PANI) has been used as an additive electrode material. In this study, a molecular-level uniform reduced graphene oxide/PANI (rGO/PANI) composite film was synthesized through self-assembly and specific thermal reduction, which showed great potential in flexible supercapacitors with high areal capacitance. The performance of the rGO/PANI film, such as specific areal capacitance and cycling stability, was significantly enhanced compared to the pure rGO electrode.
Article
Engineering, Environmental
Hewei Yuan, Yaozhong Zhang, Yanjie Su, Nantao Hu, Jianhua Yang, Min Zeng, Zhi Yang, Yafei Zhang
Summary: This study introduces a novel Type II heterojunction consisting of BiVO4 thin film and diamond-like carbon (DLC) to the PEC system, which significantly enhances the PEC water-splitting activity. Compared to the pure BiVO4, the BiVO4/DLC heterojunction exhibits increased photocurrent density and improved stability. The enhancement in PEC performance is attributed to the Type II heterojunction photoanodes that promote carrier mobility and reduce the recombination rate of electron-hole pairs. Furthermore, the sp2 carbon phase in DLC acts as a conductive channel, while the sp3 carbon phase provides stable support and passivation effect, leading to an enhancement in both PEC water splitting performance and long-time stability.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Suning Liang, Zhi Yang, Xianjun Shao, Yiming Zheng, Qiang Wang, Zhengyong Huang
Summary: This study used molecular dynamics and quantum mechanics theory to investigate the adsorption kinetics and mechanism of graphene-based materials on polar small molecules in vegetable oil. The results showed that these materials effectively adsorb the polar small molecules, and the modification with oxygen-containing groups improves their adsorption ability by converting physical adsorption to chemical adsorption. This study provides a theoretical basis for designing and preparing graphene materials with high adsorption properties.
Article
Chemistry, Multidisciplinary
Xiyu Chen, Min Zeng, Jianhua Yang, Nantao Hu, Xiaoyong Duan, Wei Cai, Yanjie Su, Zhi Yang
Summary: A 2D bimetallic phthalocyanine-based COF (COF-CuNiPc) was reported as a chemiresistive gas sensor with high gas-sensing performance for nitrogen dioxide (NO2). COF-CuNiPc with an asymmetric synergistic effect achieved a fast adsorption/desorption process to NO2. The bimetallic structure of COF-CuNiPc provided a proper band gap and the CuNiPc heterometallic active site accelerated the adsorption/desorption processes. The concept of a synergistic effect enabled by bimetallic phthalocyanines in this work can provide an innovative direction for designing high-performance chemiresistive gas sensors.
Article
Materials Science, Multidisciplinary
Yongwei Zhang, Jianhua Yang, Chunpeng Jiang, Chao Fan, Wen Lv, Xiyu Chen, Min Zeng, Nantao Hu, Tao Wang, Zhi Yang
Summary: A highly sensitive, flexible capacitive pressure sensor based on a fabric-mould strategy is introduced. Custom square-conical arrays with Au electrodes can feasibly be fabricated at scale by peeling them off the fabric mould. The pressure sensor exhibits high sensitivity, fast response/recovery time, and ultralow detection limit, showing great potential for various applications and accurately identifying human physiological information and the spatial distribution and shape of objects.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Nanoscience & Nanotechnology
Huan Yin, Tian Tian, Ruxuan Zhang, Luoxi Zhang, Mingkui Zhu, Tianhao Zhang, Zhi Yang, Nantao Hu, Yafei Zhang, Yanjie Su
Summary: All-carbon nano-heterostructure photodetectors based on different carbon allotropes exhibit excellent photoelectric performance. However, the performance is limited by the interfacial charge transfer and large dark current of graphene. In this study, asymmetric all-carbon nano-heterostructures with C-60/graphene/single-walled carbon nanotube (SWCNT) heterojunctions were designed and demonstrated to have excellent photoelectric response in the visible to NIR range, high responsivity, ultrahigh detectivity, and fast response time. The interfacial charge transfer mechanism was also investigated. This work provides insights into interfacial charge transfer in carbon-based heterostructures and offers a strategy for designing and fabricating high-performance all-carbon nano-heterostructure photodetectors.
ACS APPLIED NANO MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Huan Yin, Ruxuan Zhang, Tian Tian, Zhi Yang, Nantao Hu, Yafei Zhang, Yanjie Su
Summary: The interfacial charge transfer between single-walled carbon nanotubes (SWCNTs) and graphene is systematically investigated under different external conditions, including bias voltage, temperature, and atmosphere. It is found that electrons are transferred from SWCNTs to graphene when the applied voltage deviates from the neutral point voltage of -4 V. The built-in electric field induces the transfer of electrons from SWCNTs to graphene under various atmospheric and temperature conditions. This study provides important insights into the interfacial charge transfer between SWCNTs and graphene and offers guidance for designing high-performance all-carbon vdW heterostructure nanodevices.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Physical
Jaafar Abdul-Aziz Mehrez, Xiyu Chen, Min Zeng, Jianhua Yang, Nantao Hu, Tao Wang, Ruili Liu, Lin Xu, Yorexis Gonzalez-Alfaro, Zhi Yang
Summary: This study analyzes the structural and electronic parameters of a MoTe2/InN vdW heterostructure using density functional theory (DFT), finding that it has a higher adsorption energy and is well suited for NO2 detection. However, there are limitations in detecting NH3 and SO2.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Jaafar Abdul-Aziz Mehrez, Xiyu Chen, Min Zeng, Jianhua Yang, Nantao Hu, Tao Wang, Ruili Liu, Lin Xu, Yorexis Gonzalez-Alfaro, Zhi Yang
Summary: This study employs density functional theory to analyze the structural and electronic parameters of a MoTe2/InN vdW heterostructure. The findings indicate that the heterostructure has a strong adsorption capability for NH3, NO2, and SO2, making it well suited for NO2 detection. However, there are limitations in detecting NH3 and SO2 reliably.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Haoyuan Bai, Jingtian Hu, Shiu Hei Lam, Yanzhen Guo, Xiao-Ming Zhu, Zhi Yang, Jianfang Wang
Summary: The commonly white MoO3 is converted to a black, strongly light-absoring material through heavy V-doping, enabling efficient solar seawater desalination. The V-doped MoO3 nanospheres in the solar absorber film exhibit high evaporation rate and solar energy conversion efficiency.
ACS MATERIALS LETTERS
(2022)
Article
Chemistry, Physical
Min Hong, Bingcheng Luo, Chao Zhou, Shusheng Xu, Liying Zhang, Zili Zhang, Zhi Yang, Nantao Hu, Yafei Zhang, Zheng Liang
Summary: In this study, a hierarchical design of a film electrode based on NiCoP nanoparticles-decorated carbon nanosheet arrays assembled on nickel nanowires was successfully demonstrated to optimize the conductivity and stability of the electrode. The as-fabricated electrode exhibited high volumetric capacity, energy density, and excellent cycling performance.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
Tao Wang, Hongli Ma, Wenkai Jiang, Hexin Zhang, Min Zeng, Jianhua Yang, Xue Wang, Ke Liu, Renhua Huang, Zhi Yang
Summary: A microwave-assisted method was used to synthesize zinc oxide with controllable hierarchical structures, which showed unique response towards six kinds of gases. Pattern recognition analysis based on machine learning, such as SVM and ELM, improved the detection performance of the gas sensor array with different response characteristics regulated by the morphology. SVM achieved an accuracy of over 0.99 in distinguishing the six gases, while ELM-based regressor showed a prominent performance in predicting ethanol concentration.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)