Oxygen vacancies enriched MOF-derived MnO/C hybrids for high-performance aqueous zinc ion battery

Abstract

Manganese-based oxides are considered as a promising class of zinc storage materials. However, the dissolution problem of manganese-based oxides leads to a sharp decay of its capacity, hindering its further development. Herein, Mn-metal organic framework (Mn-MOF) derived manganese-based oxide hybrids are synthesized and developed to suppress the dissolution of manganese. The incorporation of oxygen vacancies can tune the electronic rearrangement and crystal microstructure via the different calcination atmospheres of air (Mn2O3) and Ar (MnO/C). Furthermore, the oxygen vacancy can effectively improve the conductivity, which promotes the reaction kinetics and electrochemical performance of manganese-based oxide hybrids. In addition, the storage mechanism of manganese-based oxide hybrids with oxygen vacancies on the insertion and de-intercalation of H+/Zn2+ is demonstrated. Oxygen vacancies enriched MnO/C hybrid cathode shows a high specific capacity of 336.8 mAh g−1 (0.1 A g−1) and the reversible capacity retention 73.8 % after 10,000 cycles at 1.0 A g−1, suggesting excellent long-cycle stability. Significantly, the solid-state zinc ions batteries (ZIBs) is assembled and exhibits a reversible capacity of 58.0 mAh g−1 at 1.0 A g−1. These results suggest that oxygen vacancies provide an effective strategy for exploring high-performance MOF-derived cathodes in aqueous batteries.