Structural stability and stabilization of Li2MoO3.

Due to its better physical and electrochemical properties, Li2MoO3 was proposed to replace Li2MnO3 for constructing new Li-rich cathode materials. However, the molybdenum (Mo)-ion shuttling between the Li layer and the Mo layer upon electrochemical Li-extraction raises concerns on the structural stability of the Mo-based Li-rich materials. In this article, the nudged energy band method was applied using first-principles calculations to understand the reason for the Mo-ion migration and to sieve substituent elements for Mo from a number of transition metals. Molecular dynamics calculations were performed to simulate the kinetic properties of the pristine and transition metal substituted Li2MoO3. On the basis of these calculations, antimony (Sb) was proposed as a substituent to enhance the structural stability of Li2MoO3 and improve its rate performance.