Synthesis of Self-Supported (Nicozncrfe)Se High-Entropy Selenide by Using One-Step Microwave Method for Supercapacitors and Oxygen Evolution Reaction

In this study, (NiCoZnCrFe)Se nanoparticles self-supported on nickel foam were prepared through a simple one-step microwave method. X-ray diffraction results showed that (NiCoZnCrFe)Se is a hexagonal crystal structure. Scanning electron microscopy and transmission electron microscopy were used to observe the surface and internal structure of (NiCoZnCrFe)Se and investigate the effect of varying power duration on the morphology of the material. Electrochemical test showed that the (NiCoZnCrFe)Se material had a notable capacitance (Cs) of 1365.3 F g−1, and a satisfactory capacitance retention rate of 79.1% even after 30,000 cycles. The practical energy storage effect of (NiCoZnCrFe)Se in supercapacitors was also investigated. The assembled asymmetric supercapacitor (NiCoZnCrFe)Se//AC showed good electrochemical cycling performance (80.4% after 20, 000 cycles), and the energy density reached the optimal value of 32.5 Wh kg−1. In addition, the (NiCoZnCrFe)Se material exhibited excellent oxygen precipitation performance, with an overpotential of 153.8 mV at 10 mA cm−2 and a Tafel slope of 78.9 mV dec−1. This study presents a novel concept for utilizing high-entropy selenide materials in supercapacitor energy storage and electrocatalytic applications.