Study of the degradation of the pesticide fipronil using semiconductor heterostructures of BiVO ₄ /CePO ₄ and CePO ₄ /BiVO ₄

Abstract

The use of pesticides, such as fipronil, aims to increase productivity, improve the quality of agricultural products generated, and reduce losses. However, pollutants accumulated can be loaded during rains, causing contamination in the surface and groundwater. Therefore, the combination of different semiconductors to form heterostructures can potentiate the degradation of such pollutants. BiVO₄/CePO₄ and CePO₄/BiVO₄ heterostructures were synthesized by co-precipitation method plus microwave-assisted hydrothermal treatment at 130 °C for 30 min. X-ray diffraction studies demonstrated the formation of heterostructures containing hexagonal phase (CePO₄) and scheelite and zircon-type tetragonal phases (BiVO₄). The obtained results by transmission electron microscopy and Fourier transform infrared spectroscopy results suggested the formation of an interface that contributed to the synergy between catalysts. BiVO₄/CePO₄ and CePO₄/BiVO₄ heterostructures showed degradation of 80.06% and 99.50%, respectively, of pesticide fipronil.

Keywords:
heterostructures; fipronil; bismuth vanadate; cerium phosphate