A high-efficiency dye-sensitized Pt(II) decorated metal-organic cage for visible-light-driven hydrogen production

[Display omitted] •Integrating Pt catalyst molecules into zirconium-based metal organic cages through a stepwise metalloligand.•Zr-Bpydc-PtCl2 MOC provided a quite smaller and much more stable catalytic environment for Pt catalyst.•Photocatalytic mechanism was investigated and well supported by fluorescent spectra and electrochemical data. Platinum (Pt) complexes have been tremendously exploited as efficient catalysts for producing hydrogen from water due to their high work function and redox potential, yet maximum utilization remains challenging. Herein, we have synthesized and characterized a novel Zr-Bpydc-PtCl2 MOCs material by immobilization a platinum complex in 2,2'-bipyridyl-5,5'-dicarboxylic acid-based metal-organic cages (MOCs) for the first time. In the presence of photosensitizer (Rhodamine B), the functionalized Zr-Bpydc-PtCl2 MOCs exhibits good stability and a high photocatalytic H2 evolution rate (10,466 μmol g−1 h−1) in aqueous solution, which are 6 times of Bpy-PtCl2 and 1.8 times of Bpydc-PtCl2 under visible light irradiation (λ > 420 nm), respectively. Compared with reference experiments, the good performance of Zr-Bpydc-PtCl2 MOCs indicated that integrating catalyst molecules into MOCs is a promising approach for stabilizing the catalytic center and improving the photocatalytic efficiency of H2 production in water.