Electrochemical recovery of lithium from brine by highly stable truncated octahedral LiNi0.05Mn1.95O4

Abstract

Lithium extraction from salt lakes has become a hot research issue in recent years, and LiMn2O4-based electrochemical lithium extraction is considered to be one of the most promising technologies for application. However, LiMn2O4 limits its further application due to the dissolution of Mn and the Jahn-Teller effect. In this study, a LiNi0.05Mn1.95O4 (LNMO-0.05) lithium-extraction electrode material with truncated octahedral characteristics was prepared. The special crystal surface structure enhanced the diffusion and adsorption rates of Li+, whereas Ni doping effectively suppressed the Jahn-Teller effect, and the two mechanisms synergistically enhanced the lithium extraction performance of LMO. In lithium extraction from East Taijiner brine with an Mg/Li ratio of 46, LNMO-0.05 showed excellent ion selectivity (αMg-Li = 214.08), high lithium extraction capacity (20.99 mg/g) and no significant capacity decay occurred after 10 cycles. These excellent properties make the LNMO-0.05 electrode suitable for industrial electrochemical lithium extraction.