PVP-assisted grass-like NiSe@ZnSe composite for environmental energy applications

Abstract

Well-defined NiSe@ZnSe composite electrode was synthesized along with polyvinyl pyrrolidone (PVP) and sodium lauryl sulfate (SLS) surfactant whose redox behavior is an interesting approach toward boosting performance of the supercapacitor. High crystallinity suggested that prepared composite NiSe@ZnSe was well appropriate for the application concerning the supercapacitor electrode material. The Raman spectroscopy identified the functional group, vibrations, stretching of bonds, and presence of defects in the samples. The surface to volume ratio of the loosely packed grass-like structures resulted in availability of more surface area for the electrolyte which leads to the enhanced reaction rates. As-prepared active synthesized product revealed 442 Fg−1 specific capacitance at 1 Ag−1 with 99.3% high-rate capability at 10 Ag−1 after 2000 cycles. Besides, notably, capacity retention of the sandwiched asymmetric NiSe@ZnSe//AC device was maintained to be 99.48% after constant charge−discharge 2000 cycles and displayed outstanding electrochemical stability. Herein, NiSe@ZnSe composite electrode was prepared because Zn could improve the electrical conductivity and capacitive performance. Ni can improve active site density and conductivity. Meanwhile, selenium enhanced charge transfer properties. Therefore, binary composite NiSe@ZnSe acts as a satisfactory electrode material for energy saving application.