Nanopetals shaped CuNi alloy with defects abundant active surface for efficient electrocatalytic oxygen evolution reaction and high performance supercapacitor applications

The development of durable, earth abundant and efficient materials tuned for multifunctional applications is need of the time. The assembly of low density, porous, versatile, robust and submissive copper nickel hybrid nanostructure fabricated via reduction method for oxygen evolution reaction (OER) and high performance supercapacitor applications is presented. Copper and nickel-based alloy coated on fluorinated tin oxide (FTO) with composition CuNi/FTO employed for electrochemical test recorded reduced overpotential of 294 mV to get current density of 10 mA cm⁻², high electrochemical surface area (0.087 cm²), low Tafel slope 92 mV dec⁻¹ and high specific capacitance (726 mF g⁻¹) at current density of 6 A g⁻¹. The synthesized nanostructured material maintains promising electrical linkage due to large number of catalytic sites with large surface area (130 cm² g⁻¹). First principle calculations are also performed to examine effect of Cu and Ni vacancy defects on thermodynamic stability and OER of CuNi alloy. Theoretical calculations showed that CuNi alloy with less Cu content provide easier diffusion path owing to its less defect formation energy. Current study highlights some new opening avenues on rational construction and development of cost effective with rich defects to boost the efficiency of energy devices.