Photocatalytic CO2 reduction to methanol over bismuth promoted BaTiO3 perovskite nanoparticle catalysts

The photocatalytic reduction reactions of CO2 to methanol over bismuth-promoted BaTiO3 chemical photo-catalyst were reported for the first measurement time. Catalysts were prepared via single step deposition precipitation/solution combustion technique. Phases/morphology were characterised by powder X-ray diffraction (XRD)/scanning electron microscopy (SEM). Light absorption spectrum/ bandgap energy (E-g) was calculated using ultraviolet-visible (UV-Vis) wavelength diffuse reflectance spectroscopy. The addition of Ba/Bi increased E-g. Comparing materials, synthesised by combusting, the latter showed a surface high basicity/water adsorption. Tests indicated the formation of alcohols. Bi-containing also demonstrated CO. No CH3OH was found for precipitated though. Activity resulted from the synergetic relationship effect between Bi/Ti, caused by the charge transfer mechanism between these component species, strong interaction phenomena and recombination. All were stable for a long temporal period. In the presence of the Ba or Bi metals over titania, the electrons (e(-)) from TiO2 form an e(-) - hole pair separation, prolonging their decay lifetime. Ba/Bi-based TiO2 presented produced a CH3OH yield of 5.95 mmol gcat(-1) h(-1), higher compared to structured catalytic systems, described in specific liter-ature reports. As opposed to hydrogen, CH3OH is a renewable storable liquid solar fuel, not only inte-grating carbon capture and utilisation (CCU), but also power-to-liquid. (C) 2022 Elsevier Ltd. All rights reserved.

Automated summary

The photocatalytic reduction of CO2 to methanol over bismuth-promoted BaTiO3 chemical photocatalyst was studied. Catalysts were prepared using different methods and characterized for phases and morphology. It was found that the addition of bismuth and barium improved the light absorption ability of the catalyst. Combustion-prepared samples showed higher basicity and water adsorption. The synergetic effect between bismuth and titanium resulted in the formation of methanol.