posted on 2023-11-16, 21:03authored byJiasheng Yue, Shi Chen, Yahui Wang, Anqi Zhang, Shuqiang Li, Xiaomin Han, Zhifan Hu, Ran Zhao, Chuan Wu, Ying Bai
Layered molybdenum trioxide (MoO3) is being
investigated
as a cathode material with high theoretical capacity and holds promise
for aqueous secondary batteries. Unfortunately, the severe structural
degradation of MoO3 and insufficient intrinsic properties
hinder its practical application. Herein, a Na+ preintercalation
strategy is reported as an effective method to construct cathodes
with high performance for aqueous zinc/sodium batteries (AZSBs). Compared
with pristine MoO3, the Na+ preintercalated
Na0.25MoO3 cathode delivers a reversible capacity
of 251.1 mAh g–1 at 1 A g–1, achieves
a capacity retention of 79.2% after 500 cycles, and exhibits a high
rate capability (121.5 mAh g–1 at 20 A g–1), which is superior to that in most of the previous reports. Through
the experimental measurements and density functional theory (DFT)
calculations, the preintercalation method could shorten the forbidden
band gap and modulate the electronic structure and hence effectively
inhibit the structural collapse of MoO3 microrods, induce
reversible Na+ insertion, and enhance the discharge potential.
This work is of significance for further research on molybdenum-based
compounds as cathode materials for aqueous secondary batteries.