Aqueous rechargeable zinc-ion batteries (ZIBs) have been given more and more attention because of their high specific capacity, high safety, and low cost. The reasonable design of Mn-based cathode materials is an effective way to improve the performance of ZIBs. Herein, a square block MnCO3 electrode material is synthesized on the surface of carbon cloth by a one-step hydrothermal method. The phase transition of MnCO3 was accompanied by the continuous increase of specific capacity, and finally maintained good cycle stability in the charge-discharge process. The maximum specific capacity of MnCO3 electrode material can reach 83.62 mAh g-1 at 1 A g-1. The retention rate of the capacity can reach 85.24% after 1,500 cycles compared with the stable capacity (the capacity is 61.44 mAh g-1 under the 270th cycle). Ex situ characterization indicates that the initial MnCO3 gradually transformed into MnO2 accompanied by the embedding and stripping of H+ and Zn2+ in charge and discharge. When MnCO3 is no longer transformed into MnO2, the cycle tends to be stable. The phase transformation of MnCO3 could provide a new research idea for improving the performance of electrode materials for energy devices.
Keywords: MnCO3; cyclic stability; doping; phase transformation; zinc-ion battery.
Copyright © 2022 Zheng, Liu, Yao, Gan, Li, Wang, Liu, Rao, Ma, Lv, Wang, Tao, Zhang and Wang.