Effect of homojunction structure in boosting sodium-ion storage: The case of MoO_(2)  

作　　者：Sheng Li Wei Zhang Yingxue Cui Jianmin Ma Hong-Jie Peng Jun Li Xianhu Liu Dickon HLNg Xinyan Liu Jiabiao Lian 

机构地区：[1]Institute for Energy Research,Jiangsu University,Zhenjiang 212013,Jiangsu,China [2]School of Physics and Electronics,Hunan University,Changsha 410082,Hunan,China [3]Institute of Fundamental and Frontier Sciences,University of Electronic Science and Technology of China,Chengdu 611731,Sichuan,China [4]Key Laboratory of Materials Processing&Mold(Zhengzhou University),Ministry of Education,Zhengzhou University,Zhengzhou 450002,Henan,China [5]School of Science and Engineering,The Chinese University of Hong Kong(Shenzhen),Longgang,Shenzhen 518172,Guangdong,China

出　　处：《Journal of Energy Chemistry》2023年第3期115-122,I0004,共9页能源化学（英文版）

基　　金：Financial support by National Natural Science Foundation of China(21706103 and U21A20311);Natural Science Foundation of Jiangsu Province(BK20170549);China Postdoctoral Science Foundation(2022M711381)。

摘　　要：High-efficiency sodium-ion batteries(SIBs) are in great demand for energy storage applications,which are dominated by the Na+storage performance of electrode materials.Here,a one-pot solvothermal method is developed to construct amorphous/crystalline MoO_(2)(a/c-MoO_(2)) homojunction for boosting Na+storage.Theoretical simulations signify that electrons redistribute at the homogenous interface of a/c-MoO_(2),resulting in an inbuilt driving force to easily adsorb charge carriers and promote the electron/ion transfer ability.Relying on its crystallographic superiorities,the a/c-MoO_(2)homojunction with high Na adsorbability(-1.61 eV) and low Na diffusion energy barrier(0.519 eV) achieves higher capacity(307 mA h g^(-1)at 0.1 A/g),better rate capability and cycling stability than either a-MoO_(2)or c-MoO_(2)counterpart.Combining in-situ X-ray diffraction(XRD) and ex-situ X-ray photoelectron spectroscopy(XPS)techniques,the ’adsorption-insertion-conversion’ mechanism is well established for Na+storage of MoO_(2).Our work opens new opportunities to optimize electrode materials via crystallographic engineering for efficient Na+storage,and helps to better understand the effects of homojunction structure in enhanced electrochemical performance.

关 键 词：MoO_(2)homojunction Crystallographic engineering Theoretical calculations In-situ XRD Na^(+)storage mechanism 

分 类 号：TM912[电气工程—电力电子与电力传动] TQ136.12[化学工程—无机化工]