Heterogeneous Atoms Substituted Rock Salt Phase Mn1‐xFexO Solid Solution with Rich Defects for Advanced Lithium‐Ion Batteries

Heterogeneous atoms substitution is an efficient method for promoting Li+ storage of transition metal oxides. Herein, a series of Fe-substituted MnO solid solutions with different Fe contents are synthesized by a feasible solid-phase method. The synergistic effects between heterogeneous atoms and rich vacancies are synchronously obtained, which hold distinctive electronic structures and substantial active sites. When optimized Mn0.55 Fe0.45 O solid solution as anodes for lithium-ion batteries, pre-prepared electrodes exhibit reversible lithium storage of 1286.9 mAh g-1 at 1 A g -1 after 400 cycles and even 628.1 mAh g-1 at 2 A g-1 after 1000 cycles. The LiCoO2 //Mn0.55 Fe0.45 O full cells are assembled, achieving the reversible capacity of 130.2 and 111.3 mAh g-1 after 150 cycles at 0.1 and 0.2 A g-1 , respectively. Density functional theory calculations also authenticate that the electrochemical activity can be markedly boosted by the heterogeneous atoms substituted Mn1-x Fex O solid solution.