Carbon nanotubes decorated NiSe2 nanosheets for high-performance supercapacitors

This work reports the fabrication of carbon nanotube (CNT) decorated NiSe₂ nanosheets (NiSe₂@CNT) by a rapid microwave process in 2 min. Interestingly, NiSe₂@CNT has a lamellar and tubular interwoven morphology. The specific capacitance of the prepared electrodes with different microwave conditions for supercapacitors were studied. Meanwhile, we compared the electrochemical performances of NiSe₂@CNT with the presence of different amount of CNT. The optimal NiSe₂@CNT electrode can demonstrate a high specific capacitance of 980.5 F g^-1 at a current density of 1 A g^-1 and good cycling stability of 82% retention after 9000 cycles at 5 A g^-1. In addition, an asymmetric supercapacitor was assembled by NiSe₂@CNT as positive electrode and activated carbon (AC) as negative electrode, which successfully light four white light emitting diodes (LEDs) for 6 min with an energy density of 25.61 Wh kg^-1 at a power density of 810 W kg^-1.