利用TD-DFT探究全钒液流电池正极电解液离子微观结构  

TD-DFT Method Study on ion Structure All Vanadium Flow Batter Cathode Electrolyte

作　　者：王东山 刘世伟 范华军 杜怀明 Wang Dongshan;Liu Shiwei;Fan Huajun;Du Huaiming(College of Chemical Engineering,Sichuan University of Science&Engineering,Zigong,643000)

机构地区：[1]四川轻化工大学化学工程学院,四川自贡643000

出　　处：《中国井矿盐》2023年第2期33-34,37,共3页China Well and Rock Salt

基　　金：钒钛资源综合利用四川省重点实验室科研项目(2018FTSZ13);四川轻化工大学自然科学项目(2020RC06,2021RC24);四川轻化工大学2020年研究生创新基金(y2020029)资助。

摘　　要：通过量子力学的密度泛函理论(DFT)模拟,对全钒液流电池正极电解液中可能存在的基态+4、+5价钒离子与H_(2)O、HSO_(4)^(-)、SO_(4)^(2-)基团在第一壳层结构进行探究,设定电子得失参数来模拟电池反应氧化还原过程中存在的能量变化。结果表明,单纯的价态改变并不能说明钒离子的储能性质,采用含时密度理论(TD-DFT)方式对所得模型结构进行验证,V=O(SO_(4))(H_(2)O)_(4)和V=O(HSO_(4))(SO_(4))(H_(2)O)_(3)钒离子模型反应出和紫外-可见光谱在+4、+5价态钒离子相似的峰值,两种构型之间的电压差为1.4V接近实际值1.0V。该研究对探索液钒电池微观结构和高能量密度液钒电池的制备提供了理论和实验支持。By the using of density functional theory(DFT)about the quantum chemistry,systematic study the possible+4/+5states in the first shell of vanadium ion connect with H_(2)O、HSO_(4)^(-)、SO_(4)^(2-)group.Established electronic gain or loss to simulation the battery reaction about the energy change in the oxidation-reduction process.The result showed,simply states change could not explain the storage performance of vanadium ion.Using the time-dependent density functional theory(TD-DFT)method verification each model we get,V=O(SO_(4))(H_(2)O)_(4)and V=O(HSO_(4))(SO_(4))(H_(2)O)_(3)vanadium ion model showed similar peak with+4,+5 states vanadium ion in the ultraviolet-visible spectroscopy,the voltage difference between this two structure is 1.4 V close to the real 1.0V This study provides theoretical and experimental support for the exploration of microstructure of liquid vanadium batteries and the preparation of high energy density liquid vanadium batteries.

关 键 词：密度泛函理论DFT 全钒液流电池 钒离子结构 含时密度理论 

分 类 号：TS33[轻工技术与工程]