Bi-doped twin crystal Zn0.5Cd0.5S photocatalyst for highly efficient photocatalytic hydrogen production from water

Bi doped twin crystal Zn0.5Cd0.5S (Bi/ZCS) was prepared for the first time via a facile hydrothermal method and used as a highly efficient hydrogen production photocatalyst. Our study found that Bi doping in ZCS could significantly enhance the light absorption and promote the photogenerated carrier separation and transport owing to the formation of Bi impurity level inside the bandgap of ZCS. Accordingly, the photocatalytic hydrogen production performance of ZCS was greatly improved. The optimal Bi/ZCS photocatalyst showed a very high photocatalytic hydrogen evolution rate up to 1.09 mmol h−1 (10 mg catalyst was used) and a very high apparent quantum efficiency of 31.5% at the wavelength of 420 nm. Moreover, Bi/ZCS photocatalyst also demonstrated its practical application towards photocatalytic hydrogen production from seawater, realizing a superior hydrogen evolution rate which was nearly 4 times higher than the pristine ZCS, providing an effective and low-cost way to design high-efficiency solar hydrogen production photocatalysts.