Microemulsion method synthesis of highly porous LiMn2O4 for selective lithium extraction from Salt Lakes Brine

Abstract

The spinel-structured LiMn₂O₄ (LMO) is widely recognized as a promising candidate for electrochemical lithium extraction owing to its unique three-dimensional lithium-ion diffusion pathways. However, the significant agglomeration of existing commercial lithium manganese oxide (C-LMO) poses a critical limitation on its lithium-ion loading capacity during the lithium extraction process. In this study, we successfully synthesized nano-scale pure-phase spinel LMO within a CTAB–C₆H₁₂–C₅H₁₁OH–H₂O microemulsion system. The results indicate that the LMO prepared via the microemulsion method exhibits abundant pore structures, which not only significantly reduce the Li⁺ transport distance but also enhance the contact area with the electrolyte. After 60 charge-discharge cycles, the material retains 91 % of its initial specific capacity, with a stable Coulombic efficiency ranging from 97 % to 99 %.