Mesoporous Cd1−xZnxS microspheres with tunable bandgap and high specific surface areas for enhanced visible-light-driven hydrogen generation

Abstract

Visible-light-driven splitting of water using semiconductor photocatalysts is an excellent example of sustainable chemistry. The fabrication of mesoporous photocatalysts with a narrow bandgap into the sunlight region and a high specific surface area is crucial for efficient hydrogen evolution under visible light irradiation. Herein, we describe a facile one-pot hydrothermal approach toward uniform mesoporous microspheres of Cd1−xZnxS by adopting diethylenetriamine (DETA) as the structure-directing agent. The method is facile, reproducible and allows simultaneously control of the morphology, particle size, bandgaps, as well as the specific surface area of the mesoporous microspheres Cd1−xZnxS. The photocatalytic activity on H2 production through the splitting of water without noble metal loadingis highly enhanced by the mesoporous structure feature of the products. The optimized Cd0.2Zn0.8S mesoporous microspheres exhibit a specific surface area up to 98.09m2/g and a H2 production rate of 3.43mmol/hg (about 7.62 times higher than that of pure CdS powers) under visible light irradiation. Furthermore, apparent quantum efficiency (QE) of 16.2% was achieved in the as-fabricated Cd0.2Zn0.8S mesoporous microspheres under irradiation at 420nm. This study provides an effective route toward mesoporous microspheres photocatalysts for further investigations and practical applications.