Carbon Quantum Dots Bridged TiO(2)/CdIn(2)S(4) toward Photocatalytic Upgrading of Polycyclic Aromatic Hydrocarbons to Benzaldehyde

Conversion of hazardous compounds to value-added chemicals using clean energy possesses massive industrial interest. This applies especially to the hazardous compounds that are frequently released in daily life. In this work, a S-scheme photocatalyst is optimized by rational loading of carbon quantum dots (CQDs) during the synthetic process. As a bridge, the presence of CQDs between TiO(2) and CdIn(2)S(4) improves the electron extraction from TiO(2) and supports the charge transport in S-scheme. Thanks to this, the TiO(2)/CQDs/CdIn(2)S(4) presents outstanding photoactivity in converting the polycyclic aromatic hydrocarbons (PAHs) released by cigarette to value-added benzaldehyde. The optimized photocatalyst performs 87.79% conversion rate and 72.76% selectivity in 1 h reaction under a simulated solar source, as confirmed by FT-IR and GC-MS. A combination of experiments and theoretical calculations are conducted to demonstrate the role of CQDs in TiO(2)/CQDs/CdIn(2)S(4) toward photocatalysis.