Search

Ag-polydopamine nanoparticles co-decorated defective mesoporous carbon nitride assembly with wide spectrum response is fabricated, which exhibits robust photothermal-photocatalytic H 2 production, due to Ag-PDA not only extends the light absorption of DCN, but also forms an efficient Z-scheme charge transfer path with DCN, enabling fast electron transfer. [Display omitted] • Ag-polydopamine nanoparticles co-decorated defective mesoporous carbon nitride assemblies are fabricated. • Ag-polydopamine nanoparticles co-decorated promote efficient charge transfer. • Small-sized Ag nanoparticles as efficient cocatalysts enables efficient charge separation. • Ag-polydopamine extends photoabsorption and produces obvious photothermal effect to improve catalyze activity. • The formation of Z-scheme charge transfer mechanism favors spatial charge separation. Ag-polydopamine nanoparticles co-decorated defective mesoporous carbon nitride nanosheets assemblies (Ag-PDA/DCN) with wide spectrum responseare fabricated. The Ag-PDA/DCN assemblies exhibit excellent photocatalytic hydrogen production performance. The visible light and near-infrared light driven photocatalytic hydrogen evolution rate is up to 3840 μmol h−1 g−1, which is 20 and 7 times higher than those of DCN and PDA/DCN, respectively. This is mainly because the Ag-polydopamine nanoparticles not only form an efficient carrier transport path and realize fast electron transport, but also further extend the photoresponse of DCN, resulting in an obvious photothermal effect to further improve the photocatalytic activity. More importantly, the formed Ag nanoparticles by the low-temperature photodeposition method is smaller in size and better in dispersibility. Ag nanoparticles act as a co-catalyst in Ag-PDA/DCN, which can effectively separate the spatially photogenerated charge carriers. Compared to three systems with different Ag decoration positions, Ag-PDA/DCN with Z-scheme charge transfer mechanism is more favorable for promoting photocatalytic performance. This co-decorated strategy provides a new idea for developing low-cost Pt-free photocatalysts for solar energy conversion. [ABSTRACT FROM AUTHOR]

Ni/ZnIn 2 S 4 nanosheet assembly with sulfur vacancy and Schottky junction (Ni/DZIS) is fabricated and shows much better the photocatalytic hydrogen evolution rate without any noble metal cocatalysts. The improved photocatalytic performance is mainly attributed to the synergism of sulfur vacancy and Schottky junction accelerating the photogenerated charge transfer and thus inhibiting the charge recombination. [Display omitted] • Fabrication of Ni/ZnIn 2 S 4 nanosheet assembly with sulfur vacancy and Schottky junction (Ni/DZIS) through facile ethanediol-assisted solvothermal method. • The location of Ni at the hollow site of three S atoms next to sulfur vacancy on the ZnIn 2 S 4 (0 0 6) face. • The photocatalytic hydrogen evolution rate of Ni/DZIS up to 703 μmol g−1h−1 without any noble metal cocatalysts. Surface and interface engineering play vital roles on improving the photocatalytic hydrogen evolution. Herein, Ni/ZnIn 2 S 4 nanosheet assembly with sulfur vacancy and Schottky junction (Ni/DZIS) is fabricated through facile ethanediol-assisted solvothermal method. Density functional theory (DFT) calculation reveals that the Ni is absorbed at the hollow site of three S atoms next to sulfur vacancy on the ZnIn 2 S 4 (0 0 6) face due to the formation of sulfur vacancy. The resultant Ni/DZIS Schottky junction exhibits high photocatalytic H 2 evolution rate of 703 μmol g−1h−1 without any noble metal cocatalysts, which is 2.6 times higher than that of pristine ZnIn 2 S 4 nanosheets. The improved photocatalytic performance is mainly attributed to the synergism of sulfur vacancy and Schottky junction accelerating the photogenerated charge transfer and thus inhibiting the charge recombination. Moreover, the photocatalytic performance of Ni/DZIS nearly keeps constant even after six recycles, indicating the high stability and potential applications in field of energy. This work provides a convenient strategy for constructing efficient defective heterojunction assembly photocatalysts via surface and interface engineering. [ABSTRACT FROM AUTHOR]