Empirical Confirmation of Theoretical Predictions for Amorphous H/VO4 Cathodes: Advancing Durability and Efficiency in Zinc‐Ion Batteries

Abstract

AbstractAdvancing cathode materials is crucial for the broader application of aqueous zinc‐ion batteries (ZIBs) in energy storage systems. This study presents amorphous H/VO4 (HVO), a novel cathode material engineered by substituting H+ for Mg2+ in Mg2VO4 (MgVO), designed to enhance performance of ZIBs. Initial exploration of MgVO through ab initio molecular dynamics (AIMD) simulations and density functional theory (DFT) calculations revealed a favorable Mg2+ and Zn2+ exchange mechanism. This mechanism notably reduces electrostatic interactions and facilitates ion diffusion within the host lattice. Building upon these findings, in this work, theoretical calculations analysis indicated that amorphous HVO offers a higher diffusion coefficient for Zn2+ ions and fewer electrostatic interactions compared to its crystalline MgVO precursor. Subsequent empirical validation is achieved by synthesizing amorphous HVO using a rapid ion‐exchange process, effectively replacing Mg2+ with H+ ions. The synthesized amorphous HVO demonstrated 100% capacity retention after 18000 cycles at a current density of 2 A g−1 and exhibited exceptional rate performance. These findings underscore the significant potential of HVO cathodes to enhance the durability and efficiency of aqueous ZIBs, positioning them as promising candidates for future energy storage technologies.