Regulating electrochemical performance of Cu7S4 electrodes via ligand engineering in copper cluster precursors

Abstract

Cu-based chalcogenide materials exhibit significant promise for the development of Zn-metal-free anode materials for aqueous Zn-ion batteries (AZIBs). Here, we present the establishment of an efficient and universal strategy that capitalizes on the pyrolysis of copper nanoclusters to fabricate conversion-type Cu₇S₄ anodes engineered for AZIBs, showcasing outstanding electrochemical performance. Furthermore, by exploiting ligand engineering, we enable the precise control of both the type of molecular fragments generated during nanocluster pyrolysis, thus enabling the manipulation of vacancy concentrations and ion/electron migration in the resultant pyrolysis products. In contrast to the direct pyrolysis of metal salts and ligands, the products derived from copper nanoclusters exhibit enhanced specific capacity, rate performance, and overall stability. This research offers valuable insights for the development of novel electrode materials through the pyrolysis of atomically precise nanoclusters.