ZnCdS nanoparticles decorated three-dimensional MoO3 polygonal structure: A novel photocatalyst for enhanced solar light-driven degradation of methyl orange dye

Abstract

Over the last few decades, organic dyes have been identified in trace levels in surface water, effluent, and drinking water. Photocatalysis has received enormous attention for its ability to degrade organic dyes in water. The present study includes the synthesis and characterization of a novel ZnCdS/MoO3 composite which was synthesized using a facile precipitation method. Its structural, morphological, and optical characteristics were examined through various spectroscopic and analytical techniques. Sphere-like nanoparticles of ZnCdS were well decorated on the surface of the three-dimensional polygonal structure of MoO3 which consists of stacked nanosheets. The energy band gaps of ZnCdS and MoO3 were found to be 2.52eV and 2.19eV, respectively which were favorable to form a Z-scheme heterojunction between both the components. As an effective photocatalyst, the synthesized ZnCdS/MoO3 composite exhibited optimum degradation (90.3%) of methyl orange dye which was found to be 3.22 and 13.48 times higher than pure ZnCdS and MoO3, respectively. The enhanced photocatalytic activity of ZnCdS/MoO3 was attributed mainly to the efficient separation and migration of electrons and holes across the Z-scheme heterojunction. A scavenger study was also conducted to assess the role of major radical species in the decomposition of methyl orange dye in which superoxide radicals (•O2_) demonstrated a major role. Therefore, the present study provides an effective strategy to develop polygonal structured MoO3 anchored photocatalytic materials for the enhanced removal of harmful pollutants in an aqueous phase.