Nonhierarchical Heterostructured Fe2O3/Mn2O3 Porous Hollow Spheres for Enhanced Lithium Storage

Abstract High capacity transition‐metal oxides play significant roles as battery anodes benefiting from their tunable redox chemistry, low cost, and environmental friendliness. However, the application of these conversion‐type electrodes is hampered by inherent large volume variation and poor kinetics. Here, a binary metal oxide prototype, denoted as nonhierarchical heterostructured Fe 2 O 3 /Mn 2 O 3 porous hollow spheres, is proposed through a one‐pot self‐assembly method. Beyond conventional heteromaterial, Fe 2 O 3 /Mn 2 O 3 based on the interface of (104) Fe2O3 and (222) Mn2O3 exhibits the nonhierarchical configuration, where nanosized building blocks are integrated into microsized spheres, leading to the enhanced structural stability and boosted reaction kinetics. With this design, the Fe 2 O 3 /Mn 2 O 3 anode shows a high reversible capacity of 1075 mA h g −1 at 0.5 A g −1 , an outstanding rate capability of 638 mA h g −1 at 8 A g −1 , and an excellent cyclability with a capacity retention of 89.3% after 600 cycles.