A new zinc-ion battery cathode with high-performance: Loofah-like lanthanum manganese perovskite.

Due to high safety and excellent rate performance, the aqueous Zn-ion battery is a promising energy storage battery for practical application. However, most manganese-based compounds suffer from poor cycling and rate performance. Herein, a new concept of Zn-ions battery is assembled with the loofah-like LaMnO3 perovskite as a novel cathode, achieving fast ion kinetics through the co-intercalation of Zn2+ and H+ cations. In this work, the Ni-doping strategy is adopted to improve the electrochemical performance of LaMnO3 perovskite as a cathode material for Zn-ion batteries. The resultant LaNixMn1-xO3 (x = 0.2) exhibits a superior capacity of 226 mAh g-1 after 80 cycles at 100 mA g-1 and high working voltages at 1.4 V and 1.26 V vs. Zn2+/Zn in the electrolyte of 2 M ZnSO4 + 0.2 M MnSO4. Even at 500 mA g-1, the new Zn/LaNixMn1-xO3 battery still delivers a discharge capacity of 113 mAh g-1 after 1000 cycles. At medium current density, the electrochemical process of the LaNixMn1-xO3 (x = 0.2) electrode is co-controlled by the solid diffusive and surface-capacitive process with a fast ion diffusion rate. The lanthanum manganese perovskite is a potential cathode material for Zn-ion batteries with long cycle performance and high rate cyclability. This work significantly opens up the way of perovskite materials as new cathodes for high-rate ZIBs.