B–N co-doped black TiO2 synthesized via magnesiothermic reduction for enhanced photocatalytic hydrogen production

Abstract In this work, B–N co-doped TiO2 has been synthesized by a facile fast sol-gel method, and then, a controlled magnesiothermic reduction has been developed to synthesize B–N co-doped black TiO2 under a N2 atmosphere and at 580 °C followed by acid treatment. The prepared black TiO2 samples were characterized by X-ray diffraction, high resolution transmission electron microscopy, Raman spectrameter, photoluminescence emission spectra, X-ray photoelectron spectroscopy, and ultraviolet–visible diffuse reflectance spectra. It shows that the prepared samples possess a unique crystalline core-amorphous shell structure composed of disordered surface and oxygen vacancies, and exhibit enhanced photocatalytic activity in hydrogen production in the methanol-water system in the presence of Pt as a co-catalyst. Under the full solar wavelength range of light, the maximum hydrogen production rate of the B–N co-doped black TiO2 is 18.8 mmol h−1 g−1, which is almost 4 times higher than that of pure TiO2.