Bi-functional CoCr2O4 hollow-sphere for enhanced oxygen evolution reaction and photocatalyst for harmful environmental pollutants removal

Abstract

The development of a high-performance, cost-effective, and durable multifunctional semiconductor is crucial for clean energy and environmental remediation applications such as oxygen evolution reaction (OER) and photocatalysts. In this research, we have developed a hollow sphere-based spinel-structured CoCr2O4 (HS.CCO) for bi-functional applications. These hollow spheres exhibit excellent electrocatalytic OER performance under an alkaline (1 M potassium hydroxide (KOH)) medium, which displays a higher electrocatalytic ability. The spinel hollow spheres demonstrate favorable overpotentials and Tafel potentials of 180 mV and 162 mV/dec, respectively towards OER activity. On the other hand, as a photocatalysis, they portrayed outstanding degradation efficiency under visible light irradiation towards Congo red (CR) dye degradation. Within the short treatment time higher CR degradation efficiency is achieved. These photo-electroactive spinel hollow spheres accelerate efficient OER and visible-light-driven photocatalysis with remarkable stability. They serve as an excellent example of a multifunctional heterogeneous catalyst. Finally, the obtained results indicate the current needs and future demands for enhancing the prospects of multifunctional semiconductor catalysts.