Hierarchical nanosheet-assembled copper sulfide microspheres as the cathode materials for rechargeable magnesium batteries

Abstract

Rechargeable magnesium battery is an inexpensive, high-safety energy storage technology suitable for large-scale applications. However, its development is still hindered by lacking high-performance cathode materials. Herein, we present a simple one-step template-free hydrothermal method to synthesize hierarchical CuS microspheres self-assembled from nanosheets as the cathode materials for rechargeable magnesium battery. Owing to the special structure configuration, the as-synthesized CuS microspheres can exhibit a high specific capacity of 252 mAh g–1 at 100 mA g–1, and a reversible specific capacity of 171.2 mAh g–1 at 500 mA g–1. Additionally, the CuS microspheres also show good rate capability with 91.7 mAh g–1 specific capacity at high current density of 1000 mA g–1 and a long-term cycling stability over 500 cycles. These electrochemical results indicate that the fabrication of the CuS microspheres with hierarchical structure can provide an efficient route to develop high-performance copper sulfide cathode materials for emerging rechargeable magnesium batteries.