Three-dimensional ZnS/reduced graphene oxide/polypyrrole composite for high-performance supercapacitors and lithium-ion battery electrode material

Abstract

In this work, three-dimensional ZnS/reduced graphene oxide/polypyrrole ternary composites were synthesized. The as-prepared composites are investigated as electrode materials for supercapacitors and lithium-ion batteries. For the application of supercapacitor in three electrode system, its discharge specific capacitance and energy density at 1 A/g are 1175.8 F/g and 80.0 Wh/kg after 5000 cycles, respectively. Meanwhile, its cycle stability at 1 A/g is up to 151% during 5000 loops. For the application of lithium-ion battery, its discharge specific capacitance and energy density at 100 mA/g can be up to 1446.9 mAh/g and 955.6 Wh/kg after 200 cycles, respectively. The cycle stability of the ternary composite is up to 157% at 100 mA/g during 200 loops. The excellent electrochemical performance of the composites could be ascribed to the three-dimensional structure which facilitates the penetration of the electrolyte and the insertion/extraction process of Li+ and the synergistic effect between organic and inorganic materials. The results indicate that the ZnS/reduced graphene oxide/polypyrrole composite are promising electrode materials for high-performance supercapacitors and lithium-ion batteries.