Nanosheet architecture of MnO2/carbon with improved reaction kinetics toward advanced zinc energy storage
Jiahui Peng, Huanhuan Sun, Yu Huyan, Xiang Zhang, Yuyang Gao, Honghao Ma, Jian‐Gan Wang
Abstract
Aqueous zinc ion batteries (AZIBs) hold substantial promise for large-scale energy storage system by virtue of their good safety and cost-effectiveness. However, the typical cathode material of MnO 2 is practically hampered by poor rate/cycling performance owing to its low electrical conductivity and structural fragility. Herein, a nanosheet architecture of MnO 2 /carbon is constructed via in situ rooting MnO 2 nanoarrays on carbon substrate to achieve high-rate and long-durable zinc energy storage. The unique nano-architecture significantly promotes the reaction kinetics by supplying plentiful active sites, short diffusion pathways, and improved charge transfer conductivity. The advantageous features endow the MnO 2 /carbon with remarkable rate capability (175 mAh/g at 3.0 A/g) and excellent cycling lifespan (87.8 % capacity retention after 1000 cycles at 1.0 A/g). In addition, the kinetic enhancement and fundamental reaction mechanism are systematically investigated. The encouraging results will shed new insight on designing MnO 2 -based materials to advance the development of AZIBs.