Crystalline‐Amorphous CuS@PANI Heterostructure for Enhanced Aqueous Zinc–Ion Batteries Storage Performance

ABSTRACT

Transition metal chalcogenides (TMCs) attract more attention owing to their high conductivity and controlled interlayer spacing. However, their low working voltages and rate capacity limit their practical applications. Herein, CuS@PANI was synthesized by adding the surfactant hexadecyl trimethyl ammonium bromide (CTAB) through a two‐step hydrothermal method. The CuS@PANI heterostructure and conductive polymer PANI together improve CuS@PANI cycle stability and specific capacity. The abundant amorphous region relieves volume changes during the zinc ion charge/discharge process, promotes electrolyte infiltration, and accelerates ion diffusion. Besides, zinc sulfate‐carboxymethyl cellulose (ZnSO ₄ ‐CMC) electrolyte can effectively prevent the growth of Zn dendrites to improve cycling stability. These preeminent properties make CuS@PANI exhibit high reversible capacity (230 mAh g ⁻¹ at 0.1 A g ⁻¹ ), excellent rate performance (183.9 mAh g ⁻¹ at 0.5 A g ⁻¹ and 174.8 mAh g ⁻¹ at 1 A g ⁻¹ ), and outstanding long‐term cycling stability with 97.6% capacity retention after 1300 cycles at 2 A g ⁻¹ ).