Article
Chemistry, Physical
Yuxin Deng, Ziqi Yang, Tongling Xu, Huaxing Jiang, Kar Wei Ng, Chao Liao, Danni Su, Yanli Pei, Zimin Chen, Gang Wang, Xing Lu
Summary: Due to the difficulty of p-type doping in beta-Ga2O3, the NiO/beta-Ga2O3 heterojunction is considered as a promising candidate for bipolar devices. In this study, the band alignment and electrical properties of NiO/beta-Ga2O3 heterojunctions with different beta-Ga2O3 orientations were comparatively studied. It was found that there is a type-II band alignment between NiO and beta-Ga2O3, and the valence band offsets and conduction band offsets vary with different substrate orientations. The influence of substrate orientations on the properties of NiO/beta-Ga2O3 heterojunctions is of great importance for the design and optimization of beta-Ga2O3-based heterojunction devices.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Huishan Wu, Tao Zhang, Leyun Shen, Yunze Liu, Fengzhi Wang, Jianguo Lu, Bin Lu, Xinhua Pan, Zhizhen Ye
Summary: A novel self-powered deep ultraviolet photodetector based on a SnS/Ga2O3 heterojunction modified by an ultrathin SnO layer has been developed. The device demonstrates remarkable photoelectric performance without any power supply, making it suitable for future optoelectronic applications.
ADVANCED MATERIALS INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Nasir Alfaraj, Kuang-Hui Li, Meshal Alawein, Chun Hong Kang, Laurentiu Braic, Nicolae Catalin Zoita, Adrian Emil Kiss, Tien Khee Ng, Boon S. Ooi
Summary: This article investigates the ultrahigh sensitivity and DUV photodetection capability of a hybrid oxide-nitride stack grown heterogeneously on a conductive ceramic crystal. It was found that the growth process of beta-Ga2O3 crystal on TiN introduced additional defects, resulting in DUV photodetectors with true solar-blind characteristics.
ADVANCED MATERIALS TECHNOLOGIES
(2021)
Article
Engineering, Electrical & Electronic
Jianming Lei, Qing Cai, Jiying Cao, Tongchuan Ma, Jiandong Ye, Dunjun Chen
Summary: A high-performance epsilon-Ga2O3 solar-blind photodetector was successfully fabricated using an interdigital structure. The device exhibited a prominent response peak at 240 nm and a cutoff edge at 266 nm, with a solar-blind UV in-band/out-of-band rejection ratio of 10^5 and a photo-to-dark-current ratio exceeding 10^5. The impact of varying interdigital spacing on device performance was investigated, showing that decreasing spacing increased light current and responsivity, while increasing spacing reduced dark current.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Materials Science, Coatings & Films
Ayeong Kim, Geonyeop Lee, Jihyun Kim
Summary: This study demonstrates energy-efficient capacitive sensing of deep-UV wavelengths by integrating UWBG β-Ga2O3 semiconductor with graphene electrode, eliminating the need for a solar-blind deep-UV bandpass filter. The high optical transmittance of graphene enables UV-C light absorption in β-Ga2O3, facilitating carrier transport. The photodetector shows excellent sensing performance with reproducibility and spectral selectivity at various frequencies and bias conditions.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2021)
Article
Physics, Multidisciplinary
Zheng-Nan Li, Zhao-Cai Wang, Chen Li, Bao-Lin Lu, Wei Yan, Chen-Long Huang, Tao Zhang, Yin-Hong Luo, Ren-Kui Zheng
Summary: In this study, beta-Ga2O3 epitaxial thin films with different thicknesses were grown on Al2O3 (0001) substrates using the pulse laser deposition technology. The effects of film thickness on the properties and optoelectronic characteristics of the films were investigated.
Article
Materials Science, Multidisciplinary
Wencheng Chen, Xiangyu Xu, Minghang Li, Siliang Kuang, Kelvin H. L. Zhang, Qijin Cheng
Summary: In this work, a self-powered solar-blind photodetector with a fast response is achieved using a p-GaN/i-Ga2O3/n-Ga2O3 (pin) heterojunction. The device exhibits good self-powered characteristics, high responsivity, high photo-to-dark current ratio, and fast response speed. The interfacial electronic structure between p-GaN and i-Ga2O3 is studied in detail, revealing conduction band offset and valence band offset, which contribute to the excellent device performance.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Physics, Applied
Dinusha Herath Mudiyanselage, Ramandeep Mandia, Dawei Wang, Jayashree Adivarahan, Ziyi He, Kai Fu, Yuji Zhao, Martha R. Mccartney, David J. Smith, Houqiang Fu
Summary: NiOx/beta-Ga(2)O(3) p-n heterojunctions fabricated on beta-Ga2O3 substrates exhibit distinct anisotropic electrical properties, with excellent rectification and high turn-on voltages. The device shows significant differences in specific on-resistance and reverse recovery time compared to other devices, attributed to variations in atomic configurations, density of dangling bonds, and interface trap state densities.
APPLIED PHYSICS EXPRESS
(2023)
Article
Materials Science, Multidisciplinary
Yiren Chen, Jiawang Shi, Zhiwei Zhang, Guoqing Miao, Hong Jiang, Hang Song
Summary: This paper proposes an AlGaN-based solar-blind UV heterojunction bipolar phototransistor (HBPT) with an AlGaN-based multiple quantum well (MQW) layer as the light absorption layer. The material growth, device preparation, and performance evaluation of the solar-blind UV HBPT are investigated in detail. The evaluations show that the fabricated phototransistor exhibits low dark current density, high responsivity, and quick transient response speed, supporting the feasibility of a high performance solar-blind UV photodetector based on the AlGaN-based MQW HBPT.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Materials Science, Multidisciplinary
Mengfan Ding, Kun Liang, Shunjie Yu, Xiaolong Zhao, Huihui Ren, Bowen Zhu, Xiaohu Hou, Zhiwei Wang, Pengju Tan, Hong Huang, Zhongfang Zhang, Xiaolan Ma, Guangwei Xu, Shibing Long
Summary: This study demonstrates the fabrication of flexible and heat-resistant gallium oxide deep-ultraviolet photodetectors using optimized inkjet printing. The photodetectors exhibit outstanding performance on both rigid and flexible substrates, making them highly promising for space exploration and wearable electronics.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Physics, Applied
Xin Zhou, Jinzhong Zhang, Liyan Shang, Yawei Li, Liangqing Zhu, Junhao Chu, Zhigao Hu
Summary: Self-powered flexible solar-blind photodetectors based on WSe2/beta-Ga2O3 2D/3D van der Waals (vdW) heterojunctions were manufactured, demonstrating excellent optoelectronic performances and enabling the fabrication of a solar-blind communication system with low energy consumption. Moreover, AND and OR optoelectronic logic gates were realized for signal processing in solar-blind communication.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Mei Cui, Yang Xu, Xinyu Sun, Zhengpeng Wang, Hehe Gong, Xuanhu Chen, Tiancheng Hu, Yijun Zhang, Fang-fang Ren, Shulin Gu, Jiandong Ye, Rong Zhang
Summary: In this study, Ga2O3 solar blind photodetectors with different metal-semiconductor contact configurations were constructed and their performance was compared. The Ti/Ga2O3/Ti device operated in a photoconductive mode with high responsivity and rejection ratio, but exhibited sub-gap response and high dark current. The Ni/Ga2O3/Ni device operated in a mixed photovoltaic and photoconductive mode with decent photoresponsivity, high rejection ratio, and eliminated slow photoresponse.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Review
Materials Science, Multidisciplinary
Urvashi Varshney, Neha Aggarwal, Govind Gupta
Summary: The COVID-19 pandemic has led to increased use of UV-C sterilizing devices to combat the virus, but prolonged exposure to UV-C can have harmful effects on the environment and human health. It is crucial to monitor UV-C exposure intensity and limit radiation, while developing highly sensitive solar-blind UV photodetectors to mitigate potential health risks.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Optics
Zhihua Zheng, Wen Wang, Feng Wu, Zhiyuan Wang, Maocheng Shan, Yongming Zhao, Weijie Liu, Pengcheng Jian, Jiangnan Dai, Hai Lu, Changqing Chen
Summary: Motivated by the goals of fabricating a highly reliable, high performance, and cost-efficient self-powered photodetector, researchers have developed an organic-inorganic hybrid solar-blind ultraviolet photodetector. The device exhibits high responsivity, sharp cut-off edge, and excellent detection capabilities, making it suitable for solar-blind UV detection.
Article
Engineering, Electrical & Electronic
Wei Mi, Jinze Tang, Xinrong Chen, Xinwei Li, Bingkun Li, Liyuan Luo, Liwei Zhou, Rongrong Chen, Di Wang, Jinshi Zhao
Summary: PIN-structured photodiodes were fabricated by sputtering intrinsic-Ga2O3 and n-Ga2O3 with Ti doping on p-Si substrates. The fabricated Ga2O3 films were amorphous, and the roughness increased with Ti doping concentration. The photodiodes showed high reverse breakdown voltages, significant photoelectric response to 254 nm UV light, and high responsivity at -10 V bias.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Chemistry, Physical
Namsoo Lim, Jungwook Min, Jung-Hong Min, Chun Hong Kang, Kuang-Hui Li, Tae -Yong Park, Woochul Kim, Bambar Davaasuren, Tien Khee Ng, Boon S. Ooi, Deok Ha Woo, Ji-Hyeon Park, Yusin Pak
Summary: Orthorhombic kappa-Ga2O3 is a promising ultrawide bandgap material for extreme environment devices. In this study, a kappa-Ga2O3 film was fabricated using metal organic chemical vapor deposition, and its crystallinity was analyzed by X-ray diffraction and transmission electron microscopy. The results demonstrate that this material has excellent ultraviolet-C detection capabilities.
APPLIED SURFACE SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Norah Alwadai, Zohoor Alharbi, Fatimah Alreshidi, Somak Mitra, Bin Xin, Hadeel Alamoudi, Kishor Upadhyaya, Mohamed N. Hedhili, Iman S. Roqan
Summary: This study presents a facile fabrication process for a high-responsivity solar-blind self-powered UV-C photodetector based on a p-n wide band gap semiconductor heterojunction structure. The heterojunction structure consists of solution-processed manganese oxide quantum dots (MnO QDs) as the p-type material and exfoliated Sn-doped beta-Ga2O3 microflakes as the n-type material. The resulting photodetector exhibits excellent solar-blind UV-C photoresponse characteristics and demonstrates a promising approach for the development of flexible and highly efficient UV-C devices suitable for large-scale fixable applications.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Areej Aljarb, Jiacheng Min, Mariam Hakami, Jui-Han Fu, Rehab Albaridy, Yi Wan, Sergei Lopatin, Dimitrios Kaltsas, Dipti Naphade, Emre Yengel, Mohamed Nejib Hedhili, Roaa Sait, Abdul-Hamid Emwas, Arwa Kutbee, Merfat Alsabban, Kuo-Wei Huang, Kaimin Shih, Leonidas Tsetseris, Thomas D. Anthopoulos, Vincent Tung, Lain-Jong Li
Summary: Growing continuous monolayer films of TMDs without disrupting grain boundaries is a challenge. The presence of an interfacial reconstructed (IR) layer within the substrate-epilayer gap affects the orientations of nucleating TMDs domains and materials' properties. These findings have implications for the development of TMD-based electronics and optoelectronics.
Article
Chemistry, Multidisciplinary
Saidkhodzha Nematulloev, Arunachalam Sagadevan, Badriah Alamer, Aleksander Shkurenko, Renwu Huang, Jun Yin, Chunwei Dong, Peng Yuan, Khursand E. Yorov, Azimet A. Karluk, Wasim J. Mir, Bashir E. Hasanov, Mohamed Nejib Hedhili, Naveen M. Halappa, Mohamed Eddaoudi, Omar F. Mohammed, Magnus Rueping, Osman M. Bakr
Summary: This study reports the synthesis of atomically precise copper hydride nanoclusters with a controlled defect, which were demonstrated to be highly selective catalysts for C-C cross-couplings. The work highlights the potential of defective nanoclusters as model systems for investigating individual defects, correlating defects with physicochemical properties, and rationally designing new nanoparticle catalysts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Physics, Applied
Xiao Tang, Yi Lu, Rongyu Lin, Che-Hao Liao, Yue Zhao, Kuang-Hui Li, Na Xiao, Haicheng Cao, Wedyan Babatain, Xiaohang Li
Summary: In this research, beta-Ga2O3/NiO heterostructures were directly grown on CeO2 buffered Hastelloy flexible substrates. The CeO2 buffer layer acted as a template for the epitaxial growth of single-oriented NiO and beta-Ga2O3. The resulting photodetectors on Hastelloy substrates exhibited good deformability, mechanical robustness, and high photocurrent under 284 nm light illumination.
APPLIED PHYSICS LETTERS
(2023)
Article
Optics
Sultan Alshaibani, Omar Alkhazragi, Islam Ashry, Chun Hong Kang, Mohammed Sait, Tien Khee Ng, Osman M. Bakr, Boon S. Ooi
Summary: All-inorganic CsPbBr3 nanocrystals are used to extend the field-of-view (FOV) of optical concentrators to 60 degrees, reducing the requirements of pointing, acquisition, and tracking (PAT) in optical wireless communication links. The CsPbBr3 nanocrystals convert transmitted UV light into green light that matches the peak absorption of Si-based detectors, allowing stable communication over the wide FOV.
Article
Chemistry, Multidisciplinary
Zahra Bayhan, Jehad K. El-Demellawi, Jian Yin, Yusuf Khan, Yongjiu Lei, Eman Alhajji, Qingxiao Wang, Mohamed N. Hedhili, Husam N. Alshareef
Summary: The unstable cycling performance of Mo2CTx MXene as a Li-ion battery anode is attributed to partial oxidation and structural degradation. To address this issue, a laser-induced Mo2CTx/Mo2C hybrid anode was developed, which showed improved redox kinetics, prevented structural degradation, enhanced conductivity, and improved cycling stability. The laser-induced synthesis approach demonstrates the potential of MXene-based hybrid materials for high-performance energy storage applications.
Article
Nanoscience & Nanotechnology
Noor A. Merdad, Yue Wang, Omar Alkhazragi, Zyad O. F. Mohammed, Partha Maity, Luis Gutierrez-Arzaluz, Haoze Yang, Rounak Naphade, Chun Hong Kang, Tien Khee Ng, Osman M. Bakr, Boon S. Ooi
Summary: In this study, the authors fabricated cesium lead bromide (CsPbBr3) thin films of varying thicknesses and investigated their visible-light communication (VLC) performance. Thicker films were found to have a more homogeneous surface and fewer surface trap states than thinner films. The 20-nm-thick CsPbBr3 film exhibited the best performance with a -3-dB bandwidth of 30.7 MHz and a net data rate of 330 Mb/s, making it suitable for high-power, high-speed, and large-area transmission and detection of visible-light signals.
Article
Nanoscience & Nanotechnology
Shuoyang Qiu, Jiarui Gong, Jie Zhou, Tien Khee Ng, Ranveer Singh, Moheb Sheikhi, Boon S. S. Ooi, Zhenqiang Ma
Summary: Recent demonstrations of grafted p-n junctions combining n-type GaN with p-type semiconductors have shown potential in achieving lattice-mismatch epitaxy-like heterostructures. Ultrathin dielectrics deposited by atomic layer deposition (ALD) serve as a surface passivation and quantum tunneling layer. ZrO2, with excellent properties, can be used as a high-k gate dielectric in GaN-based heterostructures. The interfacial band parameters and band-bending of Ga-polar GaN with ultrathin ALD-ZrO2 were studied, and the bandgap values of ALD-ZrO2 at different thicknesses were investigated.
Article
Engineering, Electrical & Electronic
Juan M. Marin, Islam Ashry, Abderrahmen Trichili, Omar Alkhazragi, Chun Hong Kang, Tien Khee Ng, Boon S. Ooi
Summary: Distributed fiber-optic sensors (DFOS) have been widely used, and this study demonstrates the feasibility of harvesting energy from DFOS' optical pulses and recycling the wasted optical power. The study explores the impact of pulse repetition rate on harvested power and achieves a proof-of-concept demonstration.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Jian-Xin Wang, Yue Wang, Maram Almalki, Jun Yin, Osama Shekhah, Jiangtao Jia, Luis Gutierrez-Arzaluz, Youdong Cheng, Omar Alkhazragi, Vijay K. Maka, Tien Khee Ng, Osman M. Bakr, Boon S. Ooi, Mohamed Eddaoudi, Omar F. Mohammed
Summary: Metal-organic frameworks (MOFs) are excellent platforms for high-speed and multichannel data transmission in optical wireless communications (OWCs) due to their tunable optical behaviors. In this study, a novel approach using a combination of organic linkers and metal clusters in MOFs was demonstrated to achieve a tunable wide modulation bandwidth and high net data rate. The engineered MOFs showed outstanding performance in color conversion and color-pure wavelength-division multiplexing (WDM), significantly improving the data transmission capacity and security.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Optics
Yue Wang, Jian-Xin Wang, Omar Alkhazragi, Luis Gutierrez-Arzaluz, Huafan Zhang, Chun Hong Kang, Tien Khee Ng, Osman M. Bakr, Omar F. Mohammed, Boon S. Ooi
Summary: Considerable progress has been made in underwater wireless optical communication in complex environments, especially in exploring the deep sea. The color-conversion technique offers a paradigm shift in large-area and omnidirectional light detection, improving data transmission efficiency. This study investigates difluoroboron beta-diketonate fluorophores for their photophysical properties and optical wireless communication performances.
Article
Chemistry, Physical
Lujain Alrais, Sandeep Suryabhan Gholap, Indranil Dutta, Edy Abou-Hamad, Benjamin W. J. Chen, Jia Zhang, Mohamed Nejib Hedhili, Jean-Marie Basset, Kuo-Wei Huang
Summary: Formic acid is a promising hydrogen carrier for on-demand hydrogen generation. By immobilizing a homogeneous PN3P-Ir pincer catalyst onto a support, the advantages of both homogeneous and heterogeneous catalysts can be combined. The use of cesium formate as a reaction medium and basic additive under suitable conditions significantly improves the reactivity.
APPLIED CATALYSIS B-ENVIRONMENT AND ENERGY
(2024)
Article
Chemistry, Multidisciplinary
Tariq Sheikh, Wasim J. Mir, Saidkhodzha Nematulloev, Partha Maity, Khursand E. Yorov, Mohamed Nejib Hedhili, Abdul-Hamid Emwas, Mudeha Shafat Khan, Mutalifu Abulikemu, Omar F. Mohammed, Osman M. Bakr
Summary: InAs colloidal quantum dots (CQDs) have emerged as candidate lead- and mercury-free solution-processed semiconductors for infrared technology due to their appropriate bulk bandgap and promising charge-carrier transport properties. However, the lack of suitable arsenic precursors and readily accessible synthesis conditions have limited their size and bandgap range. By controlling the reactivity, we have successfully synthesized monodisperse InAs nanorod CQDs with tunable bandgaps.
Article
Chemistry, Multidisciplinary
Lujain Alrais, Walid Al Maksoud, Baraa Werghi, Anissa Bendjeriou-Sedjerari, Edy Abou-Hamad, Mohamed N. Hedhili, Jean-Marie Basset
Summary: The synthesis of heterogeneous Ti(iv)-based catalysts for ethylene polymerization according to the concepts of surface organometallic chemistry is described. These catalysts utilize a unique silica support with a 3D fibrous morphology and an aluminum-bound hydroxyl group. The combination of morphological and electronic properties of the support leads to enhanced catalytic performance in ethylene polymerization, resulting in the formation of high-density polyethylene.
CHEMICAL COMMUNICATIONS
(2023)