Controlled synthesis of CdS micro/nano leaves with (0001) facets exposed: enhanced photocatalytic activity toward hydrogen evolution

Two-dimensional CdS micro/nano leaves have been synthesized via a controlled hydrothermal process. The dimensions of the leaves is in the range of 4–6 μm and the thickness of the leaves is 30–50 nm. The surface of the leaves is smooth and composed of several parallel laminar layers with multi-steps. The SAED and HRTEM images indicated that the surface of the leaves was mainly composed of (0001) plane and all the leaves had single-crystallinity. The morphology of the as-prepared products could be controlled by adjusting the concentration of hydrofluoric acid (HF). The effects of HF concentration, reaction temperature and time were investigated. A possible formation mechanism is proposed based on the intrinsic crystal structure and selected adsorption processes. In addition, the as-prepared CdS pinnate leaves showed enhanced photocatalytic activity toward hydrogen evolution under visible light irradiation. The efficiency of micro/nano leaves was more than 6 times greater than normal CdS microparticles.