Facilitating charge transport by phenyl-substitution and sulfate-intercalation on carbon nitride tubes for highly efficient photocatalytic hydrogen evolution

Despite challenges still remain, simultaneous regulation of light absorption, carrier separation and efficient exposed active sites of carbon nitride for the photocatalytic production of hydrogen (H 2 ) are essential to help alleviate the energy crisis and achieve carbon neutrality. Using in-plane phenyl groups doping and interlayer sulfate groups modification, we demonstrated an eco-friendly and facile method for excogitating porous tubular graphitic carbon nitride (PhSO-TCN2.5). The PhSO-TCN2.5 has hollow tubular morphology with ultrathin pore walls, which offers more exposed active sites, shortened charge diffusion path and readily available diffusion channels. More importantly, the in-plane phenyl groups doping and interlayer sulfate groups modification enabled significant intense the visible light absorption, accelerated carrier transfer due to the electron transport channel between the interlayers. Meanwhile, PhSO-TCN2.5 possesses exceptionally adjusted band gap structure and more negative conduction band potential. Accordingly, the above synergistic effects contribute to the efficient photocatalytic efficiency in H 2 evolution to 8709.29 μmol g −1  h −1 . In addition to the apparent quantum yield of 12.0% at 420 nm, that far exceeds the reported tubular and functional group-modified carbon nitride photocatalysts. This document offers guidance on designing and producing photocatalysts with high efficiency.