Metal–organic framework induced hybrid NiCo2S4/PPy structures with unique interface features for high performance flexible energy storage devices

Abstract

Designing electrodes with hybrid structures is significant for improving energy storage devices. Overall, single-component metal oxides usually show poor stability and conductivity. In order to solve this problem, based on the easy-to-modify properties of spinel-structured NiCo₂S₄, hybrid-structure NiCo₂S₄/PPy is successfully synthesized through hydrothermal synthesis and electrodeposition methods, and uniformly grown on nickel foam. Hybrid NiCo₂S₄/PPy structures exhibit a high specific capacitance of 983 C g⁻¹ at 1 A g⁻¹ and excellent stability. The assembled supercapacitor device reaches a high energy density of 76.5 W kg⁻¹ at 2984 W h kg⁻¹ and excellent cycling performance, and mechanical flexibility.