Preparation and Photocatalytic Performance of 1D/2D Co2P/g-C3N4 in Hydrogen Evolution Under Visible Light Irradiation

In this paper, using urea as raw material, g-C3N4 nanosheets were prepared by thermal oxidation stripping method, and then Co2P/g-C3N4 composite photocatalysts were prepared in situ by solvothermal and low temperature phosphating processes. The phase structure, morphology and valence state composition of the catalyst were characterized by XRD, SEM, TEM and XPS. The results indicated that a compact 1D/2D heterojunction was formed between Co2P nanorods and g-C3N4 nanosheets. The results of hydrogen evolution test showed that the hydrogen production rate of 5% Co2P/g-C3N4 composite photocatalyst was up to 1 155 μmol•h-1•g-1 under visible light irradiation (λ> 420 nm), which was 96.3 times that of pure g-C3N4, and it also showed a high stability in cycle test. Through UV-Vis diffuse reflectance spectra, photoluminescence spectra, transient photocurrent response curves and electrochemical impedance spectra characterization, it's found that Co2P closely contacted with the host g-C3N4 could broaden its light response range, and significantly promoted the migration of interface charge, restrained the recombination of photogenerated electrons and holes, consequently significantly improved the g-C3N4 photocatalytic activity of hydrogen evolution. © 2022, Materials Review Magazine. All right reserved.