Facile preparation of S-doped Cu/C core-shell composite for high-performance anode of pseudocapacitors

Abstract

A sulfur doped core-shell structure of copper and activated carbon (S-doped Cu/C) composite was synthesized by a facile water bath process followed by subsequent carbonization. The structure and morphology of the resulting composite were characterized. This core-shell structure consisted by the copper nanosphere and a layer of porous carbon. The data suggested that strong synergistic effects in S-doped Cu core and carbon shell structure prevented dissolution and passivation during the electrochemical processes. The electrochemical performances were studied after the sulfur doping. The assembled pseudocapacitors with S-doped Cu/C materials as anode and Ni-Al LDH materials as cathode exhibited excellent capacitor performances with specific capacitance reaching up to 335 F/g at the discharge current 1 A/g, as well as relevant cycling stability with ∼83% retention after 500 cycles. Overall, the proposed core-shell structure S-doped Cu/C composite is promising for use as anode material in pseudocapacitors.