One-step chemical bath co-precipitation method to prepare high hydrogen-producing active ZnxCd1-xS solid solution with adjustable band structure

Abstract A series of Zn_xCd_1−xS solid solutions were synthesized through a simple one-step chemical bath co-precipitation route. The microstructure, morphology, composition and optical properties had been thoroughly investigated. The results showed that the as-obtained Zn_xCd_1−xS samples exhibited monodisperse spherical feature. These monodisperse Zn_xCd_1−xS spheres were composed of a large number of 5–10 nm crystal grains. The chemical composition of the Zn_xCd_1−xS solid solutions can be controlled by adjusting the ratio of Zn source to Cd source and the dosage of ammonia solution. Meanwhile, the energy band structure and photocatalytic properties can be optimized. The photocatalysis experiment results revealed that the as-synthesized Zn_0.30Cd_0.70S sample exhibited optimum water splitting performance. The satisfactory hydrogen evolution rate (HER) of Zn_0.30Cd_0.70S reached 27.004 mmol g⁻¹ h⁻¹ even without any cocatalysts, which was more than 48 times that of pure CdS (0.561 mmol g⁻¹ h⁻¹). This enhancing effect can owe to the balance between light absorption capacity and redox potential caused by the incorporation of Zn in the Zn_xCd_1−xS solid solutions.