In-situ preparation of highly photocatalytic active octylimidazole functionalized CuO in deep eutectic solvent medium

Abstract

The activation of peroxymonosulfate (PMS) through various catalysts has emerged as a promising method for the degradation of organic pollutants. However, the search for effective catalysts that are both cost-efficient and easy to prepare continues to pose significant challenges. In this study, a simple approach was developed to synthesize highly active cupric oxide nanoparticles (CuO NPs) using deep eutectic solvent (DES) as the reaction medium. During the preparation, octylimidazole (OIM), a component of the DES, is adsorbed in-situ onto the surface of CuO NPs. The resulting OIM-functionalized CuO (OIM-CuO) NPs exhibited an enhanced charge transfer rate, improved separation efficiency of photogenerated electron-hole pairs and superior catalytic activity compared to pure CuO NPs. The OIM-CuO-1 NPs demonstrated a degradation efficiency exceeding 94 % for the typical dye, rhodamine B (RB) within a duration of 3.0 min under both acidic and neutral conditions. Furthermore, the catalytic performance of the synthesized OIM-CuO-1 NPs surpassed that of previously reported catalysts. Notably, the catalytic activity of the OIM-CuO-1 NPs remained stable after undergoing five consecutive degradation cycles. This research offers valuable insights into the development of highly effective complex catalysts and may facilitate the advancement of photocatalysts in the degradation of organic pollutants.