Ultrathin δ-MnO2 nanosheets as cathode for aqueous rechargeable zinc ion battery

By Cong Guo, Huimin Liu, Jingfa Li, Zhiguo Hou, Jianwen Liang, Jie Zhou, Yongchun Zhu, Yitai Qian. Electrochimica Acta, 2019

260 citations recorded by the source corpus.

Abstract Ultrathin δ-MnO 2 nanosheets were synthesized via in-situ reduction of KMnO 4 on graphene oxide using graphene oxide as both reductant and self-sacrificing template. The layered δ-MnO 2 nanosheets with a thickness of about 2–4 nm inherit the two-dimensional lamellar morphology of graphene oxide. When used as cathode for aqueous zinc ion batteries, the prepared δ-MnO 2 nanosheets exhibit a reversible capacity of 133 mAh/g at a current density of 100 mA/g over 100 cycles and a capacity of 86 mAh/g at 500 mA/g due to the layered structure and ultrathin morphology, which is much better than δ-MnO 2 microspheres. The electrochemical and structural investigation indicates a possible mechanism of two-step co-insertion of H + and Zn 2+ into the interlayer of δ-MnO 2 during discharge process. It's believed that the unique ultrathin morphology of δ-MnO 2 can well facilitate ion diffusion and structure stability during cycling, making ultrathin δ-MnO 2 nanosheets a promising cathode in aqueous zinc ion batteries.

Subfields: Electrical and Electronic Engineering, Electronic, Optical and Magnetic Materials

View Paper: https://www.semanticscholar.org/paper/ee3b85f55bd39aea5c2c385bc61f9109d9bb14c4