文献类型：期刊文献

英文题名：Electrochemical quartz crystal microbalance study of lithium-ion dynamics in LiMn2O4/λ-MnO2 for ion-selective capacitive deionization

作者：Jia, Hongkun[1]; Wang, Penglin[1]; Jin, Lei[3]; Gu, Shuai[1,2]; Yu, Jianguo[1,2]

机构：[1] National Engineering Research Center for Integrated Utilization of Salt Lake Resources, East China University of Science and Technology, Shanghai, 200237, China; [2] Joint International Laboratory for Potassium and Lithium Strategic Resources, East China University of Science and Technology, Shanghai, 200237, China; [3] The State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau, 999078, China

年份：2025

卷号：513

外文期刊名：Electrochimica Acta

收录：EI(收录号：20245217596395)

语种：英文

外文关键词：Intercalation - Intercalation compounds - Ion selective electrodes - Lithium compounds - Manganese oxide - Quartz - Redox reactions

摘要：Lithium manganese oxide (LMO) has been widely utilized in capacitive deionization (CDI) for selective lithium extraction from salt-lake brines, owing to its excellent lithium intercalation capacity, selectivity, and recovery efficiency. However, due to the lack of an in-situ detection method, the LMO electrode kinetics in aqueous solution is mainly based on deductions and inferences. Here, electrochemical workstation-quartz crystal microbalance is utilized to study the lithium dynamics in LiMn2O4/λ-MnO2 in aqueous system for the first time. In-situ electrochemical analysis verifies that the lithium intercalation and deintercalation during the redox of LiMn2O4/λ-MnO2 is a one-electron transfer quasi-reversible process. The intermediate phase, i.e., Li0.5Mn3+0.5Mn4+1.5O4 with P213 space group and layered structure, is first identified in between LiMn2O4 and λ-MnO2 with Fd3ˉm space group and spinel structures in the aqueous system. Li+ occupies the 4a and 8a sites, respectively, in Li0.5Mn3+0.5Mn4+1.5O4 and LiMn2O4. Also, the spontaneous lithiation of λ-MnO2 and faster lithiation kinetics than that of delithiation is clarified with electrochemical analyses. This research utilized the in-situ research means to interpret the lithium dynamics during the lithiation and delithiation process, which sheds light on the issues on which there is no consensus. ? 2024 Elsevier Ltd