1. Institute of Physical Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany 2. Research Center for Combustion and Environment Technology, Shanghai Jiao Tong University, Shanghai 200240, China
Surface reconstructed SrTiO3 nanocrystals were synthesized by a thermal treatment process in presence of NaBH4 and SrTiO3 nanocrystals. The surface reconstruction of SrTiO3 nanocrystals is attributed to the introduction of surface oxygen vacancies or Ti sites (such as Ti3+ and Ti2+) during the hydrogenation treatment process. The light absorption and the charge transfer ability of SrTiO3 nanocrystals are simultaneously enhanced due to surface oxygen vacancies or Ti sites (such as Ti3+ and Ti2+), which are beneficial to photocatalytic water splitting. Meanwhile, these defects also change the redox potential of the photocatalysts. Since there existed a synergistic effect between the three, the ratio of hydrogen to oxygen production was also regulated.
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