posted on 2024-02-26, 12:34authored byKai Wang, Shijia Li, Xue Chen, Jiasen Shen, Huiling Zhao, Ying Bai
Rechargeable aqueous zinc-ion batteries (AZIBs) have
been highly
desired due to their low cost, intrinsic safety, environmental friendliness,
and great potential in large-scale power storage systems. However,
their practical applications are impeded by unstable long-term electrochemical
performances induced by microstructure degradation of the cathode
material, hydrogen evolution reaction in the electrolyte, and dendritic
growth on the zinc anode upon cycling. In this work, rubidium cations
(Rb+) are introduced to synthesize an Rb+-preintercalated
NH4V4O10 (NVO-Rb) composite. The
contribution of Rb+ ions as pillars in V–O interlayers
to facilitating Zn2+ storage is investigated first, and
then the influences of partial Rb+ ions from the NVO-Rb
cathode on the aqueous electrolyte and zinc anode are specially inspected
from different viewpoints. Based on a series of characterization results,
it is comprehensively elucidated that the partial Rb+ ions
into the electrolyte suppress the generation of byproducts on the
cathode and regulate the dendrite growth on the zinc anode, thus effectively
promoting the long-term electrochemical performances of NVO-based
AZIBs. The assembled Zn∥Zn(CF3SO3)2∥NVO-Rb cell can exhibit a high specific capacity and
optimized Zn2+ diffusion kinetics, especially an improved
electrochemical cyclability with a capacity retention of 87.6% at
5 A g–1 over 10000 cycles. This study enlightens
the multiple roles of cation-preintercalation in the layered structure
material and provides a feasible strategy for the development of high-performance
aqueous batteries.