Facile fabrication of novel Cd3(C3N3S3)2/CdS porous composites and their photocatalytic performance for toluene selective oxidation under visible light irradiation

Abstract A simple hydrothermal approach was adopted for the construction of novel porous Cd3(C3N3S3)2/CdS composites that were endowed with heterojunctions. In the synthesis, Cd3(C3N3S3)2 (denoted as Cd3(TMT)2) was adopted as precursor, and a spontaneous self-decomposition process is responsible for the formation of heterojunctions and porous structure. By controlling the hydrothermal temperature and hence the level of Cd3(TMT)2 decomposition, the photocatalytic activity of the Cd3(TMT)2/CdS composites can be regulated. The composite prepared at 155 °C exhibits outstanding photocatalytic performance towards toluene selective oxidation to benzaldehyde, giving a benzaldehyde formation rate of 787 μmol g−1 h-1 under visible light (λ ≥ 420 nm) without the need of any solvent. The excellent performance is ascribed to the unique Cd3(TMT)2/CdS porous structure: large in surface area and rich in heterojunctions. In photocatalysis, the large surface area of a catalyst enables enrichment of adsorbed reactants, and the presence of heterojunctions facilitates separation and transfer of photogenerated electrons and holes. It is envisaged that the method is suitable for the generation of organic/inorganic composites for photocatalytic purposes.