The three-dimensionally ordered microporous CaTiO coupling ZnCdS quantum dots for simultaneously enhanced photocatalytic H production and glucose conversion.

Glucose conversion assisted photocatalytic water splitting technology to simultaneously produce H and high value-added chemicals is a promising method for alleviating the energy shortage and environmental crisis. In this work, we constructing type II heterojunction by in-situ coupling ZnCdS quantum dots (ZCS QDs) on three-dimensionally ordered microporous CaTiO (3DOM CTO) for photocatalytic H production and glucose conversion. The DFT calculations demonstrate that substitution of Zn on the Cd site improves the separation and transmission of photogenerated carriers. Therefore, 3DOM CTO-ZCS composite exhibits best H production performance (2.81 mmol gh) and highest apparent quantum efficiency (AQY) (5.56 %) at 365 nm, which are about 47 and 18 times that of CTO nanoparticles (NPs). The improved catalytic performance ascribed to not only good mass diffusion and exchange, highly efficient light harvesting of 3DOM structure, but also the efficient charges separation of type Ⅱ heterojunction. The investigation on photocatalytic mechanism indicates that the glucose is mainly converted to gluconic acid and lactic acid, and the control reaction step is gluconic acid to lactic acid. The selectivity for gluconic acid on 3DOM CTO-ZCS is 85.65 %. Our work here proposes a green sustainable method to achieve highly efficient H production and selective conversion of glucose to gluconic acid.