Simple Fabrication of SnO₂ Quantum‐dot‐modified TiO₂ Nanorod Arrays with High Photoelectrocatalytic Activity for Overall Water Splitting

Photoelectrochemical (PEC) water splitting has been demonstrated as a promising way to acquire clean hydrogen energy. However, the efficiency has been limited by the high recombination rate of photogenerated electron‐hole pairs. Herein, we provided a simple approach to construct a novel SnO 2 quantum dots (QDs) modified TiO 2 nanorod arrays (NAs) by the calcination of SnCl 2 ‐adsorbed TiO 2 NAs. The photocurrent density of SnO 2 QDs/TiO 2 NAs exhibits about 5 times higher than that of parent TiO 2 NAs at a bias of 0.4 V vs. Ag/AgCl. SnO 2 QDs/TiO 2 NAs also show a high photoelectrocatalytic activity for overall water splitting with an actual yield of H 2 and O 2 to be 27.85 and 11.87 μmol cm −2 h −1 , respectively. The excellent performance of photoanode for PEC water splitting could be attributed to its Z‐scheme heterostructure for good separation efficiency and transport rate of photogenerated charge carries.