Mineralization of fipronil using solar light-induced ZnO/Co3O4 photocatalyst@ceramic substrate: Optimization of parameters by RSM

Abstract

Mineralization of organic compounds especially fipronil (FP) pesticide is a major concern, while its metabolites exhibit significant toxicity, which poses a significant threat to human health and the environment. Here, ZnO, Co3O4, nanoparticles and ZnO/Co3O4 nanocomposite thin films have been fabricated on ceramic plate by spray pyrolysis method. The central composite design (CCD) method under response surface methodology (RSM) is used to optimize operational parameters and 94.95% mineralization was achieved at optimum conditions. The photocatalytic mineralization of FP pesticide has been evaluated by FTIR and UV/Vis spectroscopic techniques, and the disappearance of the main characteristics peaks indicate the mineralization of the FP pesticide. Moreover, the fabrication of catalyst over CP imparted promising reusability and stability that maintained ∼ 100% performance for the first 3 cycles of FP pesticide treatment. However, after the 3rd cycle, it began to decline and dropped to 64.03% when the 26th cycle was administered.