Significantly enhanced photocatalytic performance of CdS coupled WO3 nanosheets and the mechanism study

• A novel heterojunction CdS–WO3 photocatalyst is prepared via hydrothermal method.
• The combination of 30%-CdS–70%-WO3 results in a highly active photocatalyst for the degradation of Ciprofloxacin.
• Holes were the main active species of the CIP degradation.
• The CdS–WO3 photocatalyst has good stability.

In this report, a novel CdS–WO3 nano-heterojunction photocatalyst was successfully synthesized by a multi-step hydrothermal method. Obtained samples exhibit enhanced photocatalytic activity compared with pure WO3 and CdS for the degradation of Ciprofloxacin (CIP). Particularly, 30%-CdS–70%-WO3 sample shows the highest degradation ratio (88.85%) of CIP among all samples, which is about 3 times over the pure WO3. This activity enhancement could be attributed to the fast migration of photo-induced charge-carriers, which can sufficiently inhibit the recombination of electron–hole pairs.