Polyamidoamine Dendrimers-MoS2 Nanocomposites for Photocatalytic Degradation of Chlorpyrifos and Glyphosate Pesticides

Polyamidoamine dendrimer functionalized with MoS2 nanoparticles was synthesized and fully characterized using field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffractometry, Brunauer-Emmett-Teller, and thermal gravimetric analysis. The synthesized nanocomposite showed excellent photocatalytic activities for the degradation of two commonly used pesticides (chlorpyrifos and glyphosate). According to the optimization study, the pH value of 10 and the minimum reaction time of 110 min were required for optimal degradation of pesticides. Based on the kinetic study of the photocatalytic reaction, it was inferred that more than 95% of the pesticides were degraded into non-harmful products in less than two hours. By comparing the obtained data in this study with previous reports for photocatalytic degradation of chlorpyrifos and glyphosate, it was concluded that the present nanocomposite was able to degrade pesticides faster and more efficient than available catalysts.