A Zn0.5Cd0.5S Photocatalyst Modified by 2D Black Phosphorus for Efficient Hydrogen Evolution from Water

In this work, a photocatalyst composited of Zn0.5Cd0.5S and 2D black phosphorus (BP) nanosheets was successfully constructed for high-efficient hydrogen evolution. The structure, morphology and chemical composition of BPx/Zn0.5Cd0.5S photocatalysts were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). Remarkably, the hydrogen production rate of optimal BP15.2/Zn0.5Cd0.5S nanocomposite achieves as high as 137.17 mmol/g/h under visible light irradiation (>420 nm), which is 5 times of that of pristine Zn0.5Cd0.5S. The corresponding apparent quantum efficiency (QE) is measured to be 36.3% at 420 nm. Moreover, the hydrogen production rate reaches 26.96 mmol/g/h for BP15.2/Zn0.5Cd0.5S under the irradiation of light with wavelength longer than 510 nm. The improved photocatalytic activity can be attributed to the interfacial contact between BP and Zn0.5Cd0.5S, which efficiently promotes electron-hole pair separation. Moreover, 2D black phosphorus has successfully extended the absorption spectrum of BPx/Zn0.5Cd0.5S to the wavelength longer than 510 nm. Our result highlights the significance of BP as co-catalyst in the development of new photocatalysis for hydrogen production from water.