Aqueous Acetamiprid Degradation Using Combined Ultrasonication and Photocatalysis Under Visible Light

Abstract

Acetamiprid (ACE), a neonicotinoid pesticide widely used in pest control, was found in high concentrations in soils, rivers, and lakes. In the present study, ACE degradation was investigated using visible light driven photocatalysis over nitrogen-graphene oxide (N-GO) and palladium-graphene oxide (Pd-GO)–doped ZnO photocatalysts combined with ultrasonication implemented either as a pretreatment (sonolysis) or operated simultaneously with photocatalysis (sonophocatalysis). The effectiveness of the two ACE degradation processes was determined separately. The sonolysis pretreatment allowed reaching almost 40% acetamiprid conversion within 30 min of reaction. Pursuing with the photodegradation reaction in the presence of N-GO-ZnO and Pd-GO-ZnO resulted in a maximum conversion of 98% of ACE within 5 h. As for the sonophotocatalysis process, the reaction time was shortened from 5 to 2 h with 100% acetamiprid conversion. In addition, the photocatalysts were shown to keep their activity even after 5 sonophotocatalytic cycles, thus proving their reusability. Graphical abstract

Photocatalytic Degradation of Neonicotinoid Insecticides over Perlite-Supported TiO2

“…To restore this crystalline phase from the amorphous TiO 2 films synthesised by the sol-gel method, thermal treatment at relatively high temperatures is required after deposition, which implies a certain thermal stability [14,19]. Acetamiprid is the subject of numerous studies in the field of heterogeneous photocatalysis, although a search for the keyword "photocatalytic degradation of acetamiprid" in the Google search engine results in four times fewer results than, for example, imidacloprid as a model component [20][21][22][23][24][25][26]. However, it is very difficult to compare the results of numerous researchers due to the fact that different photocatalysts that are activated by different radiation sources are usually used, and the studies are also carried out using numerous designs of photoreactors under different operating conditions.…”