Non-noble metal Co as active sites on TiO2 nanorod for promoting photocatalytic H2 production

Abstract Non-noble metal Co was decorated on TiO2 nanorod by a photodeposition method to improve photocatalytic H2 production. Co particles with ca. 7 nm diameter dispersed well onto the TiO2 nanorods. Photocatalytic H2 production performance of Co/TiO2 was tested and the results showed that the photocatalytic activity was promoted by Co loading. The H2 evolution rate of 2.0 wt% Co/TiO2 (839.8 μmol ⋅ h−1) is 8.9 times of that of bare TiO2 (95 μmol ⋅ h−1), reaching 77.8% of that of 1.0 wt% Pt/TiO2 (1080μmol⋅h−1). Photoelectrochemical and PL measurements indicated that, like Pt cocatalyst, the loading of Co particles reduces the overpotential of H2 evolution as well as facilitates the transfer of photoinduced electrons from TiO2 to Co cocatalyst, thus improving the photocatalytic H2 evolution activity. The study not only provides a way to cut the cost of photocatalysts but gives an in-depth understanding of the effect of cocatalysts on enhancing photocatalytic H2 evolution activity.