Superexchange-induced Pt-O-Ti <sup>3+</sup> site on single photocatalyst for efficient H <sub>2</sub> production with organics degradation in wastewater
Tao Zhang, Zhiyong Zhao, Dongpeng Zhang, Xingyu Liu, Pengfei Wang, Yi Li, Sihui Zhan
Abstract
Efficient photocatalytic H 2 production from wastewater instead of pure water is a dual solution to the environmental and energy crisis, but due to the rapid recombination of photoinduced charge in the photocatalyst and inevitable electron depletion caused by organic pollutants, a significant challenge of dual-functional photocatalysis (simultaneous oxidative and reductive reactions) in single catalyst is designing spatial separation path for photogenerated charges at atomic level. Here, we designed a Pt-doped BaTiO 3 single catalyst with oxygen vacancies (BTPO v ) that features Pt-O-Ti 3+ short charge separation site, which enables excellent H 2 production performance (1519 μmol·g −1 ·h −1 ) while oxidizing moxifloxacin ( k = 0.048 min −1 ), almost 43 and 98 times than that of pristine BaTiO 3 (35 μmol·g −1 ·h −1 and k = 0.00049 min −1 ). The efficient charge separation path is demonstrated that the oxygen vacancies extract photoinduced charge from photocatalyst to catalytic surface, and the adjacent Ti 3+ defects allow rapid migration of electrons to Pt atoms through the superexchange effect for H * adsorption and reduction, while the holes will be confined in Ti 3+ defects for oxidation of moxifloxacin. Impressively, the BTPO v shows an exceptional atomic economy and potential for practical applications, a best H 2 production TOF (370.4 h −1 ) among the recent reported dual-functional photocatalysts and exhibiting excellent H 2 production activity in multiple types of wastewaters.