Cu2ZnSnS4 Nanoparticles as an Efficient Photocatalyst for the Degradation of Diclofenac in Water

Featured Application: This work has the potential to have a great impact on wastewater treatment plants. The currently adopted methods for the degradation of emerging water micropollutants, such as Diclofenac, are not efficient enough, leading to only 20–40% degradation. Our photocatalyst is a cheap and sustainable tool that allows for up to 90% degradation over 120 min, even when just using visible light sources, meaning it is superior to the dangerous UV-driven photolysis typically observed for this class of compounds. Dangerous emerging water micropollutants like Diclofenac are harming ecosystems all over the planet, and immediate action is needed. The large bandgap photocatalysts conventionally used to degrade them need to be more efficient. Cu2ZnSnS4, a well-known light absorber in photovoltaics with a bandgap of 1.5 eV, can efficiently harvest an abundant portion of the solar spectrum. However, its photocatalytic activity has so far only been reported in relation to the degradation of organic dyes, and it is usually used as a benchmark to assess the activity of a photocatalyst without testing its actual potential on a hazardous water micropollutant conventionally encountered in primary and secondary waters. Here, we report the promising photocatalytic activity of Cu2ZnSnS4 nanoparticles in the degradation of Diclofenac, chosen as a benchmark for dangerous emerging water micropollutants.