Construction of metal-organic framework-derived CeO2/C integrated MoS2 hybrid for high-performance asymmetric supercapacitor

Abstract

Metal-organic framework (MOF)-derived hybrids are promising electrode materials in electrochemical energy storage, owing to their high surface area that offers enormous redox sites and excellent conductivity. In this work, MOF-derived cerium oxide/carbon integrated with molybdenum disulfide (CeO2/C/MoS2) hybrid is developed as an electrode material for supercapacitor. Remarkably, integration of CeO2/C with small amount of MoS2 has considerably enhanced the electrochemical performance. Moreover, CeO2/C/MoS2 hybrid exhibited both surface and diffusion-controlled mechanism towards charge storage. The CeO2/C/MoS2 hybrid showed an outstanding specific capacitance (specific capacity) of 1325.67 F g−1 (397.70 C g−1) and excellent cyclic stability with capacitance retention of 92.8% after 1000 charging-discharging cycles, which is significantly higher than that of CeO2/C (727.49 F g−1) or else that of MoS2 (300.33 F g−1) at 1 A g−1. In addition, asymmetric supercapacitor (ASC) fabricated with CeO2/C/MoS2 hybrid and activated carbon (AC) showed remarkable electrochemical performance with high specific capacitance (110.55 F g−1), excellent cyclic stability (even after 1000 cycles) and high energy density of 34.55 Wh kg−1 at a power density of 666.7 W kg−1. Thus, MOF derived CeO2/C integrated MoS2 hybrid is a potential electrode material for the ASCs.