Pt-substituted Polyoxometalate Modification on Low-cost TiO2 Surface with High-efficient H2 Evolution Performance

In this work, the Pt-substituted polyoxometalate has been firstly modified on the commercial TiO2 surface forming an efficient photocatalyst with high reactivity of hydrogen evolution. During the photocatalytic process, the Pt-polyoxometalates not only increase the mobility rate of electrons but also improve the separation efficiency of photoinduced electrons and holes. After photoreduction, the in situ generated Pt0 species are anchored on the surface of polyoxometalate anion that avoid further agglomeration. Then, the in situ formed Pt0 species and polyoxometalates synergistically promote the photoinduced electron transfer efficiency from TiO2 to the protons adsorbed on the Pt0 surface. Though the content of Pt0 in the nanocomposite is only 0.6%, the photocatalytic hydrogen production rate reaches up to 5.6 mmol×g-1×h-1 and remains stable at 4.5 mmol×g-1×h-1 after the continuous catalytic process. The modification of TiO2 by Pt-substituted polyoxometalate makes the nanocomposite form a practical model to possess highly efficient photoelectric conversion performance. The presented work not only extends the family of new TiO2-polyoxometalate based materials but also makes a further step for the practical application of commercial TiO2 in photocatalytic hydrogen production.