Chemical Science International Journal

As a promising metal-free photocatalyst for hydrogen (H₂) production through water splitting under visible-light irradiation, graphitic carbon nitride (g-C₃N₄) photocatalysts decorated with CoBP was prepared via simple ultra sonification. This paper highlights the structures of the photocatalysts, their stability, rate of hydrogen evolution and the mechanism of charge transfer within the photocatalysts. The prepared C₃N₄/CoBP nanocomposite photocatalysts were characterized by using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy and UV–visible (UV–vis) diffuse reflectance spectroscopy. After detailed analysis, the C₃N₄/CoBP nanocomposite photocatalysts showed excellent photocatalytic performance, which was due to the formation of the heterostructured hybrids of g-C₃N₄ and CoBP. The effects of C₃N₄/CoBP nanohybrids on H₂ evolution were evaluated. The effects improved with increasing load of CoBP until the optimal level (5 wt% CoBP with visible-light irradiation at λ ≥420 nm). The maximum and remarkable photocatalytic H₂ evolution rate of 51.68 μmol h⁻¹ was achieved, which was 3.8 times that obtained from pure g-C₃N₄. Moreover, the C₃N₄/CoBP heterostructured nanohybrids demonstrated extremely high photostability and recyclability for H₂ evolution after visible light illumination. The composite hybrid accelerated the separation and transfer of photogenerated charge carriers and subsequently suppressed charge recombination. Conclusively, this study offered an opportunity for the design and synthesis of highly stable and efficient C₃N₄/CoBP nanocomposite photocatalysts for energy conversion and utilisation.