Preparation effects on the morphology and photocatalytic properties of carbon nitride nanotubes

Abstract Water reduction to hydrogen (H 2 ) by solar light is a green and sustainable approach to solve the energy crisis. However, conventional semiconductors usually suffer from low light absorbance and high charge recombination rate, which largely suppressed the application of this technology. Here, carbon nitride nanotubes (C 3 N 4 NTs) prepared via morphological transformation method were utilized as photocatalysts for H 2 production. The dispersed C 3 N 4 nanosheets with few layers, suitable temperature difference and heating atmosphere in the process are of great importance to the formation of well-structured nanotubes. The C 3 N 4 NTs demonstrates high visible light absorbance and efficient charge transfer kinetics, as evidenced by the UV–vis diffuse reflectance and photoluminescence spectra. In the absence of cocatalysts, a H 2 generation rate of 2.69 µmol·h −1 ·mg −1 was achieved with an apparent quantum efficiency of 2.16% at 420 nm wavelength.