Construction of Porous Carbon Nanosheet/Cu₂S Composites with Enhanced Potassium Storage

Porous C nanosheet/Cu₂S composites were prepared using a simple self-template method and vulcanization process. The Cu₂S nanoparticles with an average diameter of 140 nm are uniformly distributed on porous carbon nanosheets. When used as the anode of a potassium-ion battery, porous C nanosheet/Cu₂S composites exhibit good rate performance and cycle performance (363 mAh g⁻¹ at 0.1 A g⁻¹ after 100 cycles; 120 mAh g⁻¹ at 5 A g⁻¹ after 1000 cycles). The excellent electrochemical performance of porous C nanosheet/Cu₂S composites can be ascribed to their unique structure, which can restrain the volume change of Cu₂S during the charge/discharge processes, increase the contact area between the electrode and the electrolyte, and improve the electron/ionic conductivity of the electrode material.