School of Materials Science and Engineering, Central South University, Changsha 410083, China
Jiwu Huang
School of Materials Science and Engineering, Central South University, Changsha 410083, China
Shuquan Liang
School of Materials Science and Engineering, Central South University, Changsha 410083, China; Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province, Central South University, Changsha 410083, China; Corresponding author
Lutong Shan
School of Materials Science and Engineering, Central South University, Changsha 410083, China
Xuesong Xie
School of Materials Science and Engineering, Central South University, Changsha 410083, China
Zhenyu Yi
School of Materials Science and Engineering, Central South University, Changsha 410083, China
Yiren Wang
School of Materials Science and Engineering, Central South University, Changsha 410083, China; Corresponding author
Shan Guo
School of Materials Science and Engineering, Central South University, Changsha 410083, China
Jiang Zhou
School of Materials Science and Engineering, Central South University, Changsha 410083, China; Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province, Central South University, Changsha 410083, China; Corresponding author
Summary: Rechargeable aqueous Zn/manganese dioxide (Zn/MnO2) batteries are attractive energy storage technology owing to their merits of low cost, high safety, and environmental friendliness. However, the β-MnO2 cathode is still plagued by the sluggish ion insertion kinetics due to the relatively narrow tunneled pathway. Furthermore, the energy storage mechanism is under debate as well. Here, β-MnO2 cathode with enhanced ion insertion kinetics is introduced by the efficient oxygen defect engineering strategy. Density functional theory computations show that the β-MnO2 host structure is more likely for H+ insertion rather than Zn2+, and the introduction of oxygen defects will facilitate the insertion of H+ into β-MnO2. This theoretical conjecture is confirmed by the capacity of 302 mA h g−1 and capacity retention of 94% after 300 cycles in the assembled aqueous Zn/β-MnO2 cell. These results highlight the potentials of defect engineering as a strategy of improving the electrochemical performance of β-MnO2 in aqueous rechargeable batteries. : Energy Storage; Nanomaterials; Energy Materials Subject Areas: Energy Storage, Nanomaterials, Energy Materials
