Synthesis of Cr-doped SrTiO3 photocatalyst and its application in visible-light-driven transformation of CO2 into CH4

• Cr-doped SrTiO3 is successfully synthesized by a facile ultrasonic chemical route.
• Cr-doped SrTiO3 exhibits a large specific surface area and visible-light response.
• CO2 is photoreduced into CH4 over Cr-doped SrTiO3 under visible-light irradiation.
• Cr-doped SrTiO3 shows good stability against photoirradiation.

Visible-light-driven Cr-doped SrTiO3 was synthesized through ultrasonic chemical method. Its specific surface area is 54.3 m2 g–1 due to the relatively small particle size. X-ray diffraction pattern and X-ray photoelectron spectra confirmed the crystal structure and Sr substitution. UV–vis absorption spectra indicated that the Cr doping can lead to visible-light absorption. In addition, the oxygen vacancy in Cr-doped SrTiO3 also showed visible-light absorption. The obtained Cr-doped SrTiO3 was used to photocatalytically reduce CO2 into CH4 with a yield of 8.8 μmol g–1 after 10-h reaction. Moreover, the Cr-doped SrTiO3 exhibited good photostability.

Cr-doped SrTiO3 synthesized by ultrasonic chemical route can photoreduce CO2 into CH4 under visible-light irradiation with a yield of 8.8 μmol g−1.Figure optionsDownload as PowerPoint slide