Cu-clusters nodes of 2D metal-organic frameworks as a cost-effective noble-metal-free cocatalyst with high atom-utilization efficiency for efficient photocatalytic hydrogen evolution

Several 2D nanosheets of porphyrin MOFs with various transition-metal clusters as metal nodes were prepared via a simple solvothermal method to apply in the photocatalytic hydrogen evolution, in which the hydrogen production rate of the optimal NS-Cu was as high as 15.39 mmol•g−1•h−1. A series of experimental technologies especially cyclic voltammetry (CV) and Mott-Schottky (M-S) had been adopted to investigate the charge-transfer property of photo-generated electron-hole pairs, it was found that the uniformly dispersed Cu-clusters nodes in the original 2D MOFs played a key role in the electron transfer process, that was, the photo-generated electron transferred from excited state eosin-Y to the Cu-clusters nodes for the efficient hydrogen evolution. The excellent photocatalytic performance could be attributed to the reversible oxidation-reduction process of CuII/CuI, which had excellent electron-receiving and electron-outputting capabilities. Our results provided a novel avenue to adapt the uniformly dispersed metal nodes in the original MOFs as cost-effective noble-metal-free cocatalysts with very high atom-utilization efficiency to improve the photocatalytic hydrogen evolution performance in dye-sensitized system.