Removal of pesticide pollutants from aqueous waste utilizing nanomaterials via photocatalytic process: a review

Agrochemical pesticides have been widely used to increase the productivity of crops. The long-term persistence of pesticides is highly toxic for living system in water bodies. However, nanotechnology researchers are continuously progressing in the development of effective nanophoto-catalysts to degrade agrochemical pesticides waste. Nanoparticles lies in the semiconductor range that shows fast excitation at lower energy and generates an electron-hole mechanism. These electron-hole pairs react with hydroxide ions and molecular oxygen of water, producing free radicals and reactive species. Organic pesticides are being degraded under photocatalytic process, followed by the free radical mechanism. Due to the optimum optical behaviour, semiconducting titanium oxide, zinc oxide and their nanocomposites play an essential role in the degradation of agrochemical pesticides. Semiconducting nanomaterials or doped titanium oxides have been shown high degradation efficiency towards the agrochemical pesticides. In this way, the nanomaterials and polymer nanocomposites are used as a promising photocatalyst due to their easy availability, cost-effectiveness, good optical activity, better reusability, eco-friendly, and so on. This review highlights the recent advances in the oxidative degradation using semi-conductive nanomaterial in agricultural wastes. The Fenton oxidation process, sonolysis, and ozonolysis are summarized for environmental remediation of agrochemical pesticides from wastewater.Graphical abstractPhotocatalytic removal of agrochemical pesticides utilizing nanomaterials was proposed using visible-light-driven semiconductor materials. Semiconductors are more favourable photocatalyst due to fast electron-hole recombination that effectively degrade the pollutants.

Automated summary

Agrochemical pesticides are widely used to increase crop productivity, but their long-term persistence is highly toxic for water bodies. Nanotechnology researchers are developing effective nanophoto-catalysts to degrade agrochemical pesticide waste. Semiconducting nanomaterials or doped titanium oxides have shown high degradation efficiency for these pesticides. Nanomaterials and polymer nanocomposites are promising photocatalysts due to their availability, cost-effectiveness, optical activity, reusability, and eco-friendly properties. This review focuses on recent advances in the degradation of agrochemical pesticides in agricultural wastewater using semiconductive nanomaterials.