Room-temperature synthesis of CuxS (x = 1 or 2) co-modified TiO2 nanocomposite and its highly efficient photocatalytic H2 production activity

Abstract TiO 2 nanoparticles functionalized with Cu x S (Cu x S-TiO 2 , x = 1 or 2) photocatalysts were synthesized via a facile precipitation method at room temperature. The resulting products were well characterized by XRD, TEM, EDS, XRF, BET, XPS, UV–vis and PL. The performance of H 2 production by photocatalytic water decomposition for the Cu x S-TiO 2 nanocomposite was examined in methanol aqueous solution using a 300 W Xe lamp as light source. Results showed that the activities of the CuS and Cu 2 S dual-cocatalysts co-loaded samples exhibited highly efficient water splitting capabilities for H 2 evolution, and 5.62 mmol h −1  g −1 of H 2 production was achieved with the composition-optimized Cu x S-TiO 2 , which was more efficient than those of single cocatalyst deposited samples and TiO 2 alone. It is proposed that the co-deposition of CuS and Cu 2 S onto TiO 2 nanoparticle surface could efficiently extend light absorption toward visible light range, facilitate the separation of photoinduced charge carriers and consequently enhance the photocatalytic H 2 production activity. The present work not only shows the possibility for the simultaneous utilization of Cu x S mixtures as efficient cocatalysts and photosensitizers to significantly facilitate the photoactivity of H 2 evolution, but also offers a general, feasible strategy for constructing ternary hybrid photocatalysts with other multivalent non-noble metal compounds as cocatalysts for target applications in solar energy conversion.