Mott–Schottky Heterojunction Modulating Iron–Vanadium Oxide for High-Performance Aqueous Zinc Battery Cathodes
Yanyan Du, Yongkang Wang, Beibei Yang, Xiao Liu, Congcong Li, Wenbin Li, Panpan Zhang, Hongbin Lu, Duan Bin, Yongyao Xia
Abstract
Vanadium-based oxides have garnered significant attention for aqueous zinc batteries (AZBs), whereas sluggish Zn 2+ diffusion and structural collapse remain major challenges in achieving high-performance cathodes. Herein, different structures of iron–vanadium oxides were fabricated by modulating the amount of vanadium content. It is found that the porous Mott–Schottky heterojunction composed of Fe 0.12 V 2 O 5 and Fe 2 V 4 O 13 mixed phase was used to construct a self-generated FeVO-5 structure, which could lower the diffusion barrier and improve the electron transport derived from the formed built-in electric field at the interface, showing faster reaction kinetics and improved capacity compared with the singe-phase FeVO-1. Surprisingly, the FeVO-5 cathode delivers an impressive capacity of up to 431 mAh g –1 at 0.6 A g –1, excellent rate capability (252.3 mAh g –1, 80 A g –1 ), and superior long-term cycling performance (95% capacity retention over 12 000 cycles at 40 A g –1 ). This work presents a reasonable strategy for engineering heterostructure materials for AZB application.