Facile synthesis of spinel LiNi0.5Mn1.5O4 cathode materials using M-2(OH)(2)(C8H4O4)-class metal-organic frameworks

Abstract

Various synthesis methods have been developed to synthesize mixed metal oxide cathode materials, whereas the scale-up production is hindered by issues of complicated processes, high cost, and inhomogeneity of the prepared materials. Herein, a facile, low-cost, and scalable synthesis route using M-2(OH)(2)(C8H4O4)-class metal-organic frameworks (PTA-based MOFs) as precursors has been explored to synthesize LiNi0.5Mn1.5O4 materials with homogeneity and high crystallinity. Bimetallic PTA-based MOFs were first prepared by the reaction of metal acetates and PTA in the aqueous solution at room temperature. After thermal treatment of PTA-based MOFs, bimetal oxides (Ni-Mn-O) with the inherited morphology of porous nanoplates consisting of 20-30-nm nanoparticles were obtained. The LiNi0.5Mn1.5O4 materials prepared by calcination of Ni-Mn-O with lithium salts exhibit excellent rate capability and cycling performance, delivering a specific capacity of 115.9 mAh g(-1) at 20 C and retaining 83.8% after 500 cycles. This work opens a new way for fabrication of PTA-based MOFs and mixed metal oxides as cathode materials for lithium-ion batteries