Self‐Dispersing of (CuO_x)_n Species on Dark TiO₂ Surface as a Key to High‐Performance HER Photocatalysts

Abstract Advances in the development of photocatalytic hydrogen production are determined by the creation of technologies to synthesize highly active catalysts. In this work, a simple and effective approach to increasing the activity of defective dark TiO 2 in photocatalytic hydrogen evolution reaction (HER) is implemented, based on self‐dispersing of (CuO x ) n over the titania surface. The use of aggregated (CuO x ) n clusters obtained by pulsed laser ablation, the presence of oxygen‐deficient Ti 3+ states in dark TiO 2 playing the role of an “anchor” to fix CuO x clusters, and the presence of surface Ti 4+ –OH groups facilitating the production of atomically dispersed Cu species allow achieving high performance. The conditions of interaction between dark TiO 2 and (CuO x ) n from simple mechanical mixtures to samples obtained by impregnation determine the state and dispersing of Cu‐containing species on the catalyst surface and photocatalytic properties. The catalysts are studied by XRD, TEM, XPS, and UV–vis spectroscopy. The dispersing efficiency of (CuO x ) n on the dark TiO 2 surface correlates with the increase in the AQY in photocatalytic HER. The maximum AQY of H 2 in a water‐glycerol mixture under LED irradiation (λ = 375 nm) is 55.3%, which is comparable to the best results for the (CuO x ) n ‐TiO 2 catalysts.