Coupling of V2O5 structural design and electrolyte modulation toward stable zinc-ion battery

Abstract

Layered vanadium oxides possess abundant crystal structures and multiple redox states, which account for excellent specific capacity for zinc ion batteries (ZIBs). However, vanadium-based cathodes typically suffer from structural instability and component dissolution, leading to inferior cyclic stability and rate performance. Herein, porous V2O5 slender leaf-like nanostructure anchored on carbon cloth (CC) is synthesized via electrodeposition and subsequent calcination. Taking advantage of the distinctive hierarchical structure and the introduction of propylene carbonate (PC) electrolyte additives, the free-standing VO-C2PC electrode provides a maximum reversible capacity of 555 mA h g−1 at 0.3 A g−1, and high capacity retention of 180 mA h g−1 after 5000 cycles at 10 A g−1. Even at a high mass loading, the VO-C2PC exhibits excellent Zn storage capability and stability. Furthermore, the Zn2+ storage mechanism reveals the gradual transformation of V2O5 into stable zinc pyrovanadate (ZVO) phase, which improves the stable Zn2+ storage capability. This study provides valuable insights into the construction of advanced electrodes and the design of novel electrolytes for high-performance ZIBs.