Facile Synthesis of Metal–Organic Framework-Derived CoSe<sub>2</sub> Nanoparticles Embedded in the N-Doped Carbon Nanosheet Array and Application for Supercapacitors
Chenxu Miao, Xihao Xiao, Yan Gong, Kai Zhu, Kui Cheng, Ke Ye, Jun Yan, Dianxue Cao, Guiling Wang, Panpan Xu
Abstract
Metal–organic framework (MOF)-derived composites of transition metal oxides and porous carbon show great potential for energy storage applications. Selenylation is an effective strategy to improve the electrochemical properties of electrode materials. A facile one-step derivation and selenylation of MOFs is proposed here to obtain CoSe2 nanoparticles embedded into an N-doped carbon skeleton material (CoSe2/NC). Moreover, the composite is directly grown on nickel foam as nanosheet arrays, rather than on other materials as powders. The CoSe2/NC electrode with special construction exhibits a high capacity of 120.2 mA h g–1 at 1 A g–1 and an excellent cyclic ability of 8% loss after 10,000 cycles. An asymmetric supercapacitor CoSe2/NC-NF//AC displays a maximum energy density of 40.9 W h kg–1 at 980 W kg–1. Moreover, the device has demonstrated that it can successfully charge a mobile phone. The outstanding performance indicates promising potential of CoSe2/NC-NF electrodes for supercapacitors.