文献类型：期刊文献

英文题名：Mechanisms of sodiation in anatase TiO2 in terms of equilibrium thermodynamics and kinetics

作者：Tong, Zhongqiu Kang, Tianxing Wu, Jianming Yang, Rui Wu, Yan Lian, Ruqian Wang, Hui Tang, Yongbing Lee, Chun Sing

第一作者：Tong, Zhongqiu

通信作者：Lee, CS[1];Lee, CS[2];Lian, RQ[3]

机构：[1]Guizhou Inst Technol, Coll Mat & Met Engn, Guiyang 550003, Guizhou, Peoples R China;[2]City Univ Hong Kong, Dept Chem, Hong Kong, Peoples R China;[3]City Univ Hong Kong, Ctr Super Diamond & Adv Films COSDAF, Hong Kong, Peoples R China;[4]Hebei Univ, Sch Phys Sci & Technol, Baoding 071002, Peoples R China;[5]Chinese Acad Sci, Shenzhen Inst Adv Technol, Shenzhen 518055, Peoples R China

第一机构：贵州理工学院材料与冶金工程学院

通信机构：corresponding author), City Univ Hong Kong, Dept Chem, Hong Kong, Peoples R China;corresponding author), City Univ Hong Kong, Ctr Super Diamond & Adv Films COSDAF, Hong Kong, Peoples R China;corresponding author), Hebei Univ, Sch Phys Sci & Technol, Baoding 071002, Peoples R China.

年份：2021

卷号：3

期号：16

起止页码：4702-4713

外文期刊名：NANOSCALE ADVANCES

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000672399500001)】；

基金：This work was supported by the NSFC/RGC Joint Research Scheme 2020/21 (Project No: N_CityU104/20) and the Science and Technology Foundation of Guizhou Province of China (No. qian ke he ji chu [2017] 1065).

语种：英文

外文关键词：Anodes - Disintegration - Metal ions - Nanocrystalline materials - Oxide minerals - Phase transitions - Sodium compounds - Sodium-ion batteries - Thermodynamics - Titanium dioxide

摘要：Anatase TiO2 is a promising anode material for sodium-ion batteries (SIBs). However, its sodium storage mechanisms in terms of crystal structure transformation during sodiation/de-sodiation processes are far from clear. Here, by analyzing the redox thermodynamics and kinetics under near-equilibrium states, we observe, for the first time, that upon Na-ion uptake, the anatase TiO2 undergoes a phase transition and then an irreversible crystal structure disintegration. Additionally, unlike previous theoretical studies which investigate only the two end points of the sodiation process (i.e., TiO2 and NaTiO2), we study the progressive crystal structure changes of anatase TiO2 upon step-by-step Na-ion uptake (NaxTiO2, x = 0.0625, 0.125, 0.25, 0.5, 0.75, and 1) for the first time. It is found that the anatase TiO2 goes through a thermodynamically unstable intermediate phase (Na0.25TiO2) before reaching crystalline NaTiO2, confirming the inevitable crystal structure disintegration during sodiation. These combined experimental and theoretical studies provide new insights into the sodium storage mechanisms of TiO2 and are expected to provide useful information for further improving the performance of TiO2-based anodes for SIB applications.