Biomass‐Derived Carbon Decorated With NiSe 2 as Cathode Materials for Enhanced Supercapacitors Application

ABSTRACT The increasing demand for sustainable and efficient energy storage solutions compels the development of high‐performance supercapacitors. In this work, biomass‐derived carbon with abundant active sites and mesoporous structure was successfully prepared by a simple solvothermal synthesis method. Subsequently, carbonized spores@nickel diselenide (TPB@NiSe 2 ) nanocomposites are synthesized via a hydrothermal method. TPB‐20@NiSe 2 exhibits a specific capacitance of 767 F g −1 at a current density of 1 A g −1 and a capacity retention of 83.33% after 3,000 charge‐discharge cycles. The asymmetric supercapacitors (TPB‐20@NiSe 2 ‐3//TPB‐1), which display energy of 21.9 Wh kg −1 at 850 W kg −1 , are assembled by TPB‐20@NiSe 2 ‐3 and TPB‐1 as the cathode and anode, respectively.