Oxygen-Deficient α-MnO2 Nanotube/Graphene/N, P Codoped Porous Carbon Composite Cathode To Achieve High-Performing Zinc-Ion Batteries

Hanfang Zhang; Yihe Zhang; Yanran Liu; Xiancheng Shi; Yingge Zhang; Liqi Bai; Qi Wang; Li Sun

doi:10.1021/acsami.2c09152

Oxygen-Deficient α-MnO₂ Nanotube/Graphene/N, P Codoped Porous Carbon Composite Cathode To Achieve High-Performing Zinc-Ion Batteries

ACS Appl Mater Interfaces. 2022 Aug 17;14(32):36668-36678. doi: 10.1021/acsami.2c09152. Epub 2022 Aug 8.

Authors

Hanfang Zhang¹, Yihe Zhang¹, Yanran Liu¹, Xiancheng Shi¹, Yingge Zhang¹, Liqi Bai¹, Qi Wang¹, Li Sun¹

Affiliation

¹ Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China.

PMID: 35939330
DOI: 10.1021/acsami.2c09152

Abstract

A major drawback of α-MnO₂-based zinc-ion batteries (ZIBs) is the poor rate performance and short cycle life. Herein, an oxygen-deficient α-MnO₂ nanotube (V_O-α-MnO₂)-integrated graphene (G) and N, P codoped cross-linked porous carbon nanosheet (CNPK) composite (V_O-α-MnO₂/CNPK/G) has been prepared for advanced ZIBs. The introduction of V_O in MnO₂ can decrease the value of the Gibbs free energy of Zn²⁺ adsorption near V_O (ca. -0.73 eV) to the thermal neutral value. The thermal neutral value demonstrates that the Zn²⁺ adsorption/desorption process on V_O-α-MnO₂ is more reversible than that on α-MnO₂. The as-made Zn/V_O-α-MnO₂ battery is able to deliver a large capacity of 305.0 mAh g^-1 and high energy density up to 408.5 Wh kg^-1. The good energy storage properties can be attributed to V_O. Additionally, the V_O-α-MnO₂/CNPK/G composite possesses the structure of nanotube arrays, which results from the vertical growth of α-MnO₂ nanotubes on CNPK. This unique array structure helps to realize fast ion/electron transfer and stable microstructure. The electrochemical performance of V_O-α-MnO₂ has been comprehensively improved by compositing with G and CNPK. The V_O-α-MnO₂/CNPK/G can achieve capacity up to 405.2 mAh g^-1, energy density of 542.2 Wh kg^-1, and long cycle life (80% capacity retention after 2000 cycles).

Keywords: carbon; graphene; oxygen-deficient; zinc-ion battery; α-MnO2 nanotube.