Mechanical and thermodynamical stability of BiVO4 polymorphs using first-principles study

作     者：A K M Farid UI Islam Md Nurul Huda Liton H M Tariqul Islam Md Al Helal Md Kamruzzaman 

作者机构：Department of Computer Science and Engineering Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Chemistry Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics and Materials Science and Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong Kong Hong Kong SAR China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2017年第26卷第3期

页      面：395-403页

核心收录：

学科分类：07[理学] 

主　　题：BiVO4 crystal structure lone pair mechanical stability 

摘      要：First principles calculations of structural, electronic, mechanical, and thermodynamic properties of different poly- morphs of BiVO4 are performed using Bender-type plane/wave ultrasoft pseudopotentials within the generalized gradient approximation （GGA） in the flame of density functional theory （DFT）. The calculated structural and electronic properties are consistent with the previous theoretical and experimental results. The electronic structures reveal that m-BiVO4, op- BiVO4, and st-BiVO4 have indirect band gaps, on the other hand, zt-BiVO4 has a direct band gap. From the DOS and Mulliken＇s charge analysis, it is observed that only m-BiVO4 has 6s2 Bi lone pair. Bond population analysis indicates that st-BiVO4 shows a more ionic nature and a similar result is obtained from the elastic properties. From the elastic prop- erties, it is observed that st-BiVO4 is more mechanically stable than the others, st-BiVO4 is more ductile and useful for high electro-optical and electro-mechanical coupling devices. Our calculated thermodynamic properties confirm the similar characteristics found from electronic and elastic properties, m-BiVO4 is useful as photocatalysts, solid state electrolyte, and electrode and other polymorphs are applicable in electronic device fabrications.