Achieving solar-to-hydrogen evolution promotion using TiO2 nanoparticles and an unanchored Cu co-catalyst

Abstract Spherical Cu particles were successfully synthesized by a facile strategy at room temperature. The crystal phase and structure were characterized by XRD, SEM, and TEM measurements. The physical mixing of the as-synthesized copper spheres with TiO2 nanoparticles could initial and promote solar-to-hydrogen evolution in methanol aqueous solution. TEM result showed that the partial of Cu co-catalyst attached on the surface of the host TiO2 nanoparticles, although the interface of TiO2-Cu non-existed in the synthetic process. On the basis of photo/electro-chemical measurements, it was proposed that charge transfer was accomplished via collisions between the TiO2 and Cu nanoparticles, which promoted charge separation and subsequently photocatalytic hydrogen evolution in the suspension.