Photocatalysis by metal doped semiconductor is attracting major attention to enable the reduction of CO2(g) in the presence of water vapor as a hole scavenger. Such technology has the potential to produce chemical feedstock and simultaneously minimize environmental pollution. Potassium doped iron oxide (α-Fe2O3) of varying potassium compositions (100 Fe:x K, 0 ≤ x ≤ 5) are synthesized using incipient wetness impregnation method. The structure, composition, and properties of the catalysts are investigated by X-ray diffraction, nitrogen adsorption-desorption experiments, DSC, TGA, and multiple spectroscopies, including: DRUV-vis, FTIR, Raman, ICP-AES, XPS and UPS, TEM with EDS and SAED. UV-visible light (λ ≥ 295 nm) excited the catalysts uniformly deposited in a cylindrical photoreactor in presence of pure CO2 or air (400 ppm CO2), both under a saturated water vapor atmosphere. The maximum production of CO(g) (RCO = 0.5836 μmol gcat-1 h-1 in pure CO2 and RCO = 0.4267 μmol gcat-1 h-1 in air) quantified by GC-TCD-FID corresponds to 100Fe:1K photocatalyst. The surface doped potassium photocatalyst enhances the photocatalytic efficiency by creating a more negative conduction band than the CO2/CO reduction potential as supported by UPS and DRUV-vis spectroscopies. The photoreduction mechanism and also the effects of scavenger species will be reported.

Photocatalytic CO2 reduction with potassium doped iron oxide

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.