In-situ Cutting of Graphene into Short Nanoribbons with Applications to Ni-Zn Batteries.

Rechargeable Ni-Zn batteries, with high safety, low cost and nontoxicity, can be expected to compete with lithium-ion batteries for market share. However, the issue of dissolution of zinc electrode largely limit the battery cycle life and remains unsolved. We designed a kind of graphene-ZnO hybrid electrode in which in-situ cutting of graphene into short nanoribbons can effectively anchor plenty of zinc atoms onto the surface of graphene. This not only thoroughly fixes the issue of dissolution of zinc electrode but also increases the specific surface areas of zinc and promotes chemical reaction rate of the charge-discharge processes. By performing experimental measurements, we found that the discharge capacity of the new designed Ni-Zn batteries can be as high as 2603 mAh/g, and the superior electrochemical performance can be kept in 10,000 test cycles, suggesting that the new developed in-situ cutting technique is very useful in electrochemical fields.