Fabrication of well-dispersed Pt nanoparticles onto the donor-acceptor type conjugated polymers for high-efficient photocatalytic hydrogen evolution

It is still challenging to fabricate photocatalysts via loaded metal cocatalysts with good dispersion onto the conjugated polymers (CPs). Herein, a donor-acceptor (D-A) structural CP of PyDTDO-3 was employed to host platinum (Pt) nanoparticles (NPs) using N, N'-dimethylformamide (DMF) as a protectant, stabilizer, and reducing agent, which not only promotes Pt NPs to have excellent dispersion property on the surface of PyDTDO-3 but also endows Pt NPs to maintain metallic Pt0 species. As a result, the PyDTDO-3 loaded with Pt NPs exhibits remarkable hydrogen (H-2) evolution activity with a rate of 39.9 mmol g(-1) h(-1) under visible light irradiation, and the fair stability of optimal 7% Pt/PyDTDO-3 is expressed in the rate of H2 generation upon 30 h cycling. Based on density functional theory (DFT) calculations, it has been demonstrated that Pt NPs are selectively loaded onto the acceptor (A) unit of PyDTDO-3 that has the lowest adsorption energies (E-ads) and the closest bond lengths between the Pt NPs and PyDTDO-3. Moreover, there are much more electrons filling at the Fermi level (E-f), indicating the optimal 7% Pt/PyDTDO-3 with high electroconductivity timely captured and removed the photoinduced electrons and thus realized the space separation efficiency of electron-hole pairs. Overall, our findings offer a rational way to load metal cocatalysts onto CPs with good dispersion for efficient photocatalytic H2 evolution.