A metal–organic framework approach to engineer mesoporous ZnMnO3/C towards enhanced lithium storage

Abstract

Bimetal oxides with high theoretical capacities are one of the promising candidates for lithium-ion batteries (LIBs), yet they show lower cycling stability due to the inherent large volume effect and slow transport kinetics during the lithiation/delithiation process. Thus, to address these issues a simple MOF-5 templated strategy was developed to fabricate mesoporous ZnMnO₃/C and to demonstrate it as an advanced anode material for LIBs. ZnMnO₃/C was simply synthesized by solvothermal and subsequent carbonization processes. Benefiting from the electron transfer from carbon to ZnMnO₃, the title anode material could efficiently reduce polarization, facilitate Li⁺ transfer, enhance pseudocapacitive storage, and bring about excellent lithium storage performance, including superior reversible capacity, good rate capability, and long-lasting cycling stability. The results of Raman spectroscopy and density functional theory (DFT) calculations confirmed that after compounding with carbon, the band gap of ZnMnO₃ decreased, and the adsorption of Li⁺ increased, which enhances the excellent electrochemical performances of ZnMnO₃/C.