Tiny Ni0.85Se nanosheets modified by amorphous carbon and rGO with enhanced electrochemical performance toward hybrid supercapacitors

Abstract Considering that electrode materials for supercapacitors suffer poor cycling stability and low electrons transfer at high current density, combination with carbonaceous materialhas has been devoted to strengthen the conductivity and improve the specific power and specific energy. Herein, the Ni0.85Se@C/rGO composite with tiny Ni0.85Se nanosheeets anchoring on rGO and coated by amorphous carbon has been successfully synthesized via programmed temperature controlling. As combined with dual modified carbon, which not only can ensure the electric connection of all the tiny Ni0.85Se nanosheets, but also provide confinement to inhibit disintegration, the Ni0.85Se@C/rGO//AC supercapacitor device shows a thrilling specific energy of 45.6 Wh kg−1 and 31.4 Wh kg−1 at specific power of 463.5 W kg−1 and 9.4 kW kg−1, respectively.