ZIF-8-coated CdS popcorn -like photocatalyst with enhanced visible -light -driven photocatalytic activity for degradation of toluene

In this paper, a visible-light-driven ZIF-8-coated CdS popcorn-like photocatalyst that can degrade toluene continuously and stably was successfully synthesized by controlling the preferential construction of 2-methylimi-dazole ligands on the PVP-coated CdS surface. A structural and morphological analysis showed that a popcorn -like photocatalyst with rich porosity and increased specific surface area was formed by self-assembly ZIF-8 around CdS. The photocatalytic efficiency of the ZIF-8-coated CdS popcorn-like photocatalysts remained at 81.44 % after five photocatalytic cycles. In the process of photocatalytic degradation, the degradation efficiency was influenced by the flow velocity, relative humidity and initial concentration. Among these factors, the relative humidity played a crucial role because toluene was easily oxidized by the ?OH radicals contributed by water. Analysis of the Mott-Schottky (M?S) plots suggested that the formation of an n-n-type structure between CdS and ZIF-8 facilitated the conversion of toluene gas under visible light illumination.

Automated summary

A visible-light-driven ZIF-8-coated CdS popcorn-like photocatalyst was successfully synthesized by controlling the preferential construction of ligands, showing high efficiency and stability. The photocatalytic efficiency of the ZIF-8-coated CdS popcorn-like photocatalysts remained high after five cycles, with relative humidity playing a crucial role in the degradation process.