Water oxidation without sacrificial agent over Eu ions doping BaSnO3

In this work, oxygen evolution from pure water is successfully carried out under light irradiation in the presence of hydrogen reduced Eu-doped BaSnO₃ (HEB) without any sacrificial agent. The presence of Eu³⁺/Eu²⁺ self-redox couples are benefit for the improvement of the absorption and the charge transfer. The radical trapping and electron paramagnetic resonance experiments confirm that O₂⁻ and h⁺ are the main active species. The Eu ions doping can promote electrons-transfer to sustainable production of O₂⁻. The efficient consumption of electrons is benefit for separation of the photogenerated charge carriers. Therefore, the photogenerated holes can be transferred to H₂O and then produce oxygen.