Uniformly assembling n-type metal oxide nanostructures (TiO2 nanoparticles and SnO2 nanowires) onto P doped g-C3N4 nanosheets for efficient photocatalytic water splitting

[Display omitted] •PCN and NMOs hybrid (NMOs/PCN) architectures are obtained by a self-assembly route.•NMOs/PCN exhibit delicate architectures where NMOs uniformly distribute on PCN.•NMOs as efficient electron transporting channels can extract electrons from PCN.•NMOs/PCN present enhanced electron-hole separation efficiency.•Non/low-Pt-assisted NMOs/PCN show prominent visible-light-driven HER activity. Exploitation of g-C3N4 based photocatalysts capable of drastically boosting photoinduced electron-hole separation and solar-to-H2 conversion efficiency consequences is a hotspot topic. Herein, a construction of few-layer P-doped g-C3N4 (PCN) nanosheets decorated with n-type metal oxides (NMOs) nanostructures, i.e. TiO2 nanoparticles and SnO2 nanowires via a self-assembly method is reported. NMOs uniformly distributing on PCN act as electron transporting channels, dramatically enhancing extraction efficiency of photogenerated electrons from PCN. The resultant TiO2/PCN and SnO2/PCN in the absence of Pt under visible light irradiation exhibit drastically enhanced H2 evolution reaction (HER) rates of 1082 and 2090 μmol h−1 g−1 comparing with PCN (132 μmol h−1 g−1). Such HER activities are superb among noble metal-free g-C3N4 based photocatalysts. Under a very low Pt amount (0.33 wt%), the HER rates of TiO2-Pt/PCN and SnO2-Pt/PCN further climb up to 11,632 and 12,469 μmol h−1 g−1.