Article
Instruments & Instrumentation
Le Yu, Tingyu Liu, Gaiping Lian
Summary: The study investigated the influence of oxygen vacancies on the optical properties of cadmium tungstate crystals, calculated the defect formation energies of oxygen vacancies with different charges, and obtained the absorption and emission peaks of F center and F+ center. The results showed that the calculated absorption peaks were close to the experimental results, suggesting a correlation between these prominent absorption peaks and oxygen vacancies.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
(2021)
Article
Materials Science, Ceramics
R. Z. Huang, Y. Y. Wei, T. F. Gao, C. M. Li, C. H. Jiang
Summary: Investigations on vacancy-ordered structures of pure and doped delta-Bi2O3 reveal that the structure with combined <110> and <111> vacancy arrangements is energetically favorable. Different doping ions tend to occupy specific sites, with larger ions favoring Bi(2) sites and smaller ions favoring Bi(1) sites. The electronic structure of oxides can be tuned by vacancy and interstitial defects to enhance conductivity and photocatalytic properties.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Ceramics
Hepeng Wang, Xiangping Jiang, Chao Chen, Xiaokun Huang, Xin Nie, Li Yang, Wenying Fan, Shaotian Jie, Hui Wang
Summary: By doping CeO2, the crystal structure of Ca1-xCexBi2Nb1.75(Cu0.25W0.75)(0.)O-25(9) ceramics transformed from orthorhombic phase to pseudotetragonal phase, with weakened lattice distortion and increased oxygen vacancies. The CBNCW-0.04Ce ceramic showed excellent comprehensive properties, making it a promising candidate for high-temperature piezoelectric applications.
CERAMICS INTERNATIONAL
(2022)
Article
Engineering, Electrical & Electronic
Ru-xi Sun, Ting-yu Liu, Chun-yu Shi, Jia-mei Song, Kai-li Wu
Summary: In this study, the effect of oxygen vacancy on the electronic structure and optical spectra of SrO crystals was investigated using first-principles calculation. It was found that the oxygen vacancy introduces a deep impurity level and causes a red shift in the absorption spectrum of SrO crystals.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Timofey Perevalov, Igor P. Prosvirin, Evgenii A. Suprun, Furqan Mehmood, Thomas Mikolajick, Uwe Schroeder, Vladimir A. Gritsenko
Summary: This study investigated the atomic and electronic structure of Hf0.5Zr0.5O2 and Hf0.5Zr0.5O2:La thin films, revealing similar electronic structures and a bandgap of about 5.4 eV. The presence of oxygen vacancies in the bombarded films was evaluated by comparing experimental valence band photoelectron spectra with theoretical calculations.
JOURNAL OF SCIENCE-ADVANCED MATERIALS AND DEVICES
(2021)
Article
Chemistry, Multidisciplinary
Huijun Chen, Chaesung Lim, Ting Tan, Mengzhen Zhou, Lei Zhang, Xiang Sun, Zuyun He, Yongjian Ye, Xiaobao Li, Hui Zhang, Jeong Woo Han, Chenghao Yang, Yan Chen
Summary: Nanoparticle exsolution from perovskite-based oxides matrix upon reduction has been used as a platform for designing high-activity catalysts. In this study, the critical impact of the exsolution process on the local surface electronic structure was demonstrated using Pr0.4Sr0.6Co0.2Fe0.7Nb0.1O3 thin film as the model system. Advanced microscopy and spectroscopy techniques revealed that the band gaps of both the oxide matrix and exsolved nanoparticles decreased during exsolution, leading to good electrocatalytic activity for fuel oxidation.
Article
Materials Science, Multidisciplinary
Xie Huang, Qiao Wu, Rong Dai, Jing Ning, Lei Zhang, Wei Wang, Suqing Xue, Junfeng Yan, Fuchun Zhang, Weibin Zhang
Summary: Based on first-principles density functional theory, the electronic structure, optical and lattice dynamical properties of AgGaS2 crystal were calculated. The results demonstrate that AgGaS2 is a promising infrared nonlinear optical crystal with good nonlinear optical coefficient and suitable birefringence.
RESULTS IN PHYSICS
(2022)
Article
Energy & Fuels
Chenxi Zhao, Wenjun Zhu, Changhai Liang
Summary: This study investigates the influence of different crystalline ZrO2 supports on the catalytic performance of NiMo/ZrO2 catalyst for hydrodeoxygenation. Monoclinic ZrO2 is found to exhibit better catalytic activity and selectivity. NiMo/m-ZrO2 shows higher hydrogenation conversion and liquid alkanes selectivity, as well as excellent catalytic stability.
Article
Chemistry, Physical
Yong He, Lei Zhang, Hui-Wen Xiong, Xiao Kang
Summary: Oxygen deficiency has a significant impact on the lattice defects in nickel ferrite spinel crystals, resulting in the generation of non-stoichiometric nickel ferrite containing oxygen vacancies (NiFe2O4-delta). As the sintering temperature increases, the concentration of oxygen vacancies in NiFe2O4-delta increases, leading to an increase in lattice parameter. Furthermore, the tendency for NiFe2O4-delta to decompose into Ni alloy and Fe3O4 during sintering was observed.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Ceramics
Xiaodong Wei, Guoliang Hou, Yulong An, Pan Yang, Xiaoqin Zhao, Huidi Zhou, Jianmin Chen
Summary: This paper investigated the effects of CeO2 and Sc2O3 doping on YSZ, where CeO2 increased cell volume and tetragonal degree while Sc2O3 had the opposite effect. The results showed that co-doping with CeO2 and Sc2O3 improved thermal conductivity and provided stability against phase transformation, making CeScYSZ an ideal material for thermal protection at higher temperatures.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
A. Vasanth Rao, K. Narsimha, G. Swarupa, N. Anuradha, B. Kranthi Kumar, D. Ravinder Reddy, G. Upender, B. Vijaya Kumar
Summary: In this study, Sn-doped CdWO4 nanorods were successfully prepared and their photocatalytic activity in dye degradation was evaluated. XRD analysis and HRTEM images confirmed the structure and morphology of the materials. The optimal photocatalytic activity was observed in the sample with a doping concentration of 3 mol% Sn-doped CdWO4, attributed to its large surface area and oxygen vacancies.
Article
Chemistry, Physical
Miao He, Jianping Long, Minglu Li, Ruixin Zheng, Anjun Hu, Dayue Du, Yu Yan, Zhiqun Ran, Longfei Ren, Runjing Li, Chuan Zhao, Xiaojuan Wen, Haoyang Xu, Chaozhu Shu
Summary: Electronic structural engineering, through introduction of exotic dopant and vacancy, enhances the catalytic activity of CoSe2 nanosheets for oxygen redox reactions. Fe dopant and Co defects promote electron delocalization and reduce the adsorption energy of LiO2 intermediate, improving the electrocatalytic activity. The synergistic effect between Co vacancy and Fe dopant optimizes the electronic structure of Co ion and reduces the energy barrier of oxygen electrode reactions. Lithium-oxygen batteries based on Fe-CoSe2-V-Co electrodes exhibit high Coulombic efficiency, large discharge capacity, and excellent cycling life.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Chemistry, Physical
Yamin Feng, Lingling Sun, Zhiwen Qi, Yan Zhang, Gaoliang Wang, Wenning Gao, Weifeng Liu
Summary: This study demonstrates an effective strategy to enhance the electrochemical performance of CoO by introducing multiple defects, improving the electrical conductivity and redox activity.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Physics, Applied
Jinlin Bao, Lu Yang, Sisong Jiang, Yan Wang
Summary: This study systematically investigates the effects of vacancy defects and torsion on the optoelectronic properties of single-layered 1T-TaS2 using the first-principles method. Vacancy defects cause local distortions and changes in bond length, and the formation energy of the VS system is lower than the V2S system, making it easier to achieve a single sulfur-atom vacancy in experiments. Torsion opens a narrow bandgap, with the VS system showing a decreasing trend in the range of 2-8 degrees and the V2S systems continuously increasing. The optical properties of 1T-TaS2 monolayer are closely related to defects and torsion, showing an increase in static dielectric constant, the maximum of the imaginary part, initial absorption coefficient, and reflectivity with torsion.
MODERN PHYSICS LETTERS B
(2023)
Article
Chemistry, Physical
F. Mazzola, H. Hassani, D. Amoroso, S. K. Chaluvadi, J. Fujii, V. Polewczyk, P. Rajak, Max Koegler, R. Ciancio, B. Partoens, G. Rossi, I. Vobornik, P. Ghosez, P. Orgiani
Summary: WO3 is a versatile compound that undergoes structural transitions, with various applications such as flexopiezoelectricity, electrochromism, and improving Li-based battery performance. The synthesis of WO3 thin films holds promise for stabilizing electronic phases, but its electronic structure remains unexplored experimentally. This study investigates the electronic structure of strained WO3 thin films and reveals the Fermiology of the system, with significant energy splittings due to atomic distortions. These splittings and the system's thermal stability offer potential for controlling inter- and intraband scattering in electronic applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Inorganic & Nuclear
Xiuwen Zhou, Benjamin J. Powell
INORGANIC CHEMISTRY
(2018)
Article
Chemistry, Inorganic & Nuclear
Premkumar Gnanasekaran, Yi Yuan, Chun-Sing Lee, Xiuwen Zhou, Alex K-Y. Jen, Yun Chi
INORGANIC CHEMISTRY
(2019)
Article
Chemistry, Multidisciplinary
Ling-Yang Hsu, Qiumin Liang, Zhiheng Wang, Hsin-Hung Kuo, Wun-Shan Tai, Shi-Jian Su, Xiuwen Zhou, Yi Yuan, Yun Chi
CHEMISTRY-A EUROPEAN JOURNAL
(2019)
Article
Nanoscience & Nanotechnology
Wun-Shan Tai, Premkumar Gnanasekaran, Yi-Yang Chen, Wen-Yi Hung, Xiuwen Zhou, Tai-Che Chou, Gene-Hsiang Lee, Pi-Tai Chou, Caifa You, Yun Chi
Summary: A new class of bis-tridentate Ir(III) complexes was synthesized and their emission tuning between the ultraviolet and blue region was rationalized using time-dependent density functional theory (TD-DFT) approaches. A highly efficient blue emitter was successfully synthesized and used to fabricate practical blue-emitting OLEDs with superior performance.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Caifa You, Xue-Qi Wang, Xiuwen Zhou, Yi Yuan, Liang-Sheng Liao, Yu-Chan Liao, Pi-Tai Chou, Yun Chi
Summary: In this study, two series of deep-blue-emitting homoleptic iridium(III) phosphors were synthesized using a different strategy to achieve high yields. The phosphors were examined through various spectroscopic and structural analysis methods, revealing their potential as deep-blue emitters for OLEDs. OLED devices based on these phosphors showed promising external quantum efficiencies and emission characteristics.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Inorganic & Nuclear
Ze-Lin Zhu, Premkumar Gnanasekaran, Jie Yan, Zhong Zheng, Chun-Sing Lee, Yun Chi, Xiuwen Zhou
Summary: Four blue-emissive iridium(III) complexes have been successfully synthesized and employed as both an emissive dopant and a sensitizer in OLED devices. These complexes exhibit bis-tridentate architectures and show excellent luminescent properties and electronic transition characteristics.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Ryuichi Murase, Timothy A. Hudson, Thomas S. Aldershof, Ky V. Nguyen, Jan G. Gluschke, Elise P. Kenny, Xiuwen Zhou, Tiesheng Wang, Martin P. van Koeverden, Benjamin J. Powell, Adam P. Micolich, Brendan F. Abrahams, Deanna M. D'Alessandro
Summary: This article introduces the multi-step redox properties and optical/electrochromic behavior of the two-dimensional framework [Cu(BTDAT)(MeOH)]. By using electron paramagnetic resonance and visible-near infrared spectroelectrochemistry, the mechanism for multi-step redox processes is elucidated. Computational band structure calculations predict delocalized electronic transport in the framework, suggesting that [Cu(BTDAT)(MeOH)] is a Mott insulator.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Materials Science, Multidisciplinary
Xiaomei Peng, Chia-Hsiu Yeh, Sheng Fu Wang, Jie Yan, Shifeng Gan, Shi-Jian Su, Xiuwen Zhou, Ye-Xin Zhang, Yun Chi
Summary: Near-infrared emitting Os(II) complexes with improved emission properties and increased radiative lifetime are successfully developed by introducing 4-(trifluoromethyl)phenyl on pyrazine. The influence of C-H(D) stretching vibrations on non-radiative transition processes is confirmed, leading to the fabrication of efficient NIR organic light-emitting diodes.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Xilin Yang, Xiuwen Zhou, Ye-Xin Zhang, Deli Li, Chensen Li, Caifa You, Tai-Che Chou, Shi-Jian Su, Pi-Tai Chou, Yun Chi
Summary: Four isomeric iridium metal complexes were successfully synthesized, and acid-induced isomerization was discovered to transform one isomer to another. Different isomers showed different effects on emission spectra. High photoluminescent efficiency and color coordinates were achieved in devices based on two isomeric compounds. OLEDs with one of the isomeric compounds as a sensitizing phosphor also exhibited high luminescence efficiency.
Article
Materials Science, Multidisciplinary
Yanyan Qin, Xilin Yang, Jibiao Jin, Deli Li, Xiuwen Zhou, Zhong Zheng, Yingjie Sun, Wai-Yeung Wong, Yun Chi, Shi-Jian Su
Summary: This study designs and reports two new carbene complexes with stabilized energy levels, leading to OLED devices with high electroluminescence efficiency.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Jibiao Jin, Zelin Zhu, Jie Yan, Xiuwen Zhou, Chen Cao, Pi-Tai Chou, Ye-Xin Zhang, Zhong Zheng, Chun-Sing Lee, Yun Chi
Summary: In this research, a series of blue-emitting Ir(III) phosphors based on cyclometalating N-heterocyclic carbenes (NHCs) were reported. Experimental and theoretical characterization showed that these emitters have high photoluminescence quantum yields, short radiative lifetimes, and excellent photophysical characteristics. Furthermore, high-efficiency blue and true-blue hyperphosphorescent OLEDs were successfully achieved by utilizing these phosphors.
ADVANCED PHOTONICS RESEARCH
(2022)
Article
Chemistry, Physical
Xiuwen Zhou, Benjamin J. Powell
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2020)
Article
Chemistry, Organic
Yingnan Zhao, Jie Ding, Xiao Han, Ting Geng, Xiuwen Zhou, Chen Hu, Yashu Wang, Guanjun Xiao, Bo Zou, Hongwei Hou
ORGANIC CHEMISTRY FRONTIERS
(2020)
Article
Materials Science, Multidisciplinary
Wun-Shan Tai, Ling-Yang Hsu, Wen-Yi Hung, Yi-Yang Chen, Chang-Lun Ko, Xiuwen Zhou, Yi Yuan, Alex K. -Y. Jen, Yun Chi
JOURNAL OF MATERIALS CHEMISTRY C
(2020)
Article
Chemistry, Applied
Robert Wawrzinek, Xiuwen Zhou, Mujeeb Ullah, Ebinazar B. Namdas, Shih-Chun Lo
Article
Physics, Condensed Matter
Shivani Gohri, Jaya Madan, Rahul Pandey
Summary: This study improves the efficiency of SnS-based solar cells by implementing the glancing angle deposition approach and introducing a CZTSSe layer. The findings offer valuable insights for enhancing the design of SnS-based solar cells and making them more efficient.
SOLID STATE COMMUNICATIONS
(2024)
Article
Physics, Condensed Matter
Mahboubeh Yeganeh, Davoud Vahedi Fakhrabad
Summary: The lattice thermal conductivity of CdO monolayer was investigated, and it was found to be lower than that of bulk CdO due to the lower phonon lifetime and phonon group velocity. As a result, the monolayer exhibits higher thermoelectric efficiency compared to the bulk counterpart.
SOLID STATE COMMUNICATIONS
(2024)
Article
Physics, Condensed Matter
Shivam Srivastava, Prachi Singh, Anjani K. Pandey, Chandra K. Dixit
Summary: In this research paper, a novel equation of state (EOS) based on finite strain theories is proposed for predicting the thermo elastic properties of various materials. Extensive analysis and comparison with existing models and experimental data demonstrate the validity and effectiveness of the proposed EOS in capturing the unique thermodynamic behavior of nanomaterials, bulk metallic glasses, and superconductors. This research is of great importance in the fields of materials science, nanotechnology, and condensed matter physics.
SOLID STATE COMMUNICATIONS
(2024)
Article
Physics, Condensed Matter
Subrata Das, Sanjoy Kr Mahatha, Konstantin Glazyrin, R. Ganesan, Suja Elizabeth, Tirthankar Chakraborty
Summary: In this study, we investigated the structural evolution of Tb2Ti2O7 under external pressure and temperature, and confirmed the occurrence of an isostructural phase transition beyond 10 GPa pressure. This transition leads to changes in lattice parameters and mechanical properties, which can be understood in terms of localized rearrangement of atoms.
SOLID STATE COMMUNICATIONS
(2024)
Article
Physics, Condensed Matter
Hamze Mousavi
Summary: It has been found that undoped graphene sheet has zero states at the Fermi energy level, making it difficult for Cooper pairing to occur in the superconductive state. However, T-graphene, with physical properties similar to graphene, exhibits metallic behavior and has available electron states near the Fermi level. The gap equation for the s-wave superconductive state is derived based on the attractive Hubbard model and the Bogoliubov de Gennes equation for this two-dimensional metallic system. It is found that a nonzero critical temperature, τ, exists for different levels of electron-electron interaction, ǫ. τ has higher values when the system has electronic half band-filling, but decreases when the system does not have half band-filling. However, τ vanishes when ǫ becomes small enough near the band edges.
SOLID STATE COMMUNICATIONS
(2024)