Effective doping of phosphorus in copper sulfide for high performance energy storage devices

Phosphorus (P) doping is an efficient approach for modifying the physicochemical characteristics of transition metal sulfides by causing lattice distortion, enhancing electronic conductivity, and providing more active sites for charge storage. Here, a facile hydrothermal method for effective phosphorus doping in copper sulphides are reported. XRD, FESEM, EDX spectrum, BET, UV, and Raman spectroscopy were used to characterize the synthesised CuS and P-CuS. Electrochemical analysis was done with a 2 M KOH electrolyte in techniques like CV, GCD and EIS. P-CuS exhibits hexagonal topology and 656 F/g specific capacitance at 1 A/g. An asymmetric supercapacitor device was fabricated by utilizing hexagonal shaped P doped copper sulfide as a positive electrode and activated carbon as a negative electrode and at 2 A/g, it attains 28.537 Wh/kg of energy density at 642.08 W/kg of power density and good sustainability with 80 % capacitance retained over 800 cycles. This research gives us a wider look on how we can build these types of electrode materials for forthcoming energy storage devices. [Display omitted] •Hexagonal shaped nanocrystals of CuS and P-CuS is fabricated by hydrothermal method.•P-CuS exhibit superior capacitive performance with a high specific capacitance of 656 A/g at 1 A/g current density.•The ASC device of P-CuS//AC exhibit high energy density of 28.537 Wh/kg at 642.08 W/kg.•Fabricated ASC device displays excellent retention of 80 % after 800 GCD cycles.•Doping of hetero atom in copper sulfide plays a major role in tuning the electrochemical properties.