title: CO2reduction over NaNbO3and NaTaO3perovskite photocatalysts.
abstract: The activity of NaNbO3and NaTaO3perovskites for the photocatalytic reduction of CO2is studied in this work. For this purpose, sodium niobate and tantalate have been prepared using solid-state reactions, extensively characterised by means of powder X-ray diffraction, UV-vis, photoluminescence and Raman spectroscopies and N2adsorption isotherms, and tested in the gas-phase reduction of CO2under UV light in a continuous flow photoreactor. NaNbO3is constituted of an orthorhombically distorted perovskite structure, while a ca. 4.5 : 1 combination of the orthorhombic and monoclinic modifications is found in the tantalate. Both catalysts exhibit interesting intrinsic activities, with the tantalate material giving rise to a slightly higher performance. This is attributed to a compromise situation between electron-hole recombination and the reducing potential of conduction band electrons. In addition, a decrease in the competition of water protons for photogenerated electrons is observed with both catalysts with respect to TiO2.
authors.affiliation: Photoactivated Processes Unit, IMDEA Energy Institute, Móstoles Technology Park, Avenida Ramón de la Sagra, 3, 28935 Móstoles, Madrid, Spain. fernando.fresno@imdea.org victor.delapenya@imdea.org.
authors.forename: F
authors.initials: F
authors.lastname: Fresno
authors.affiliation: Thermochemical Processes Unit, IMDEA Energy Institute, Móstoles Technology Park, Avenida Ramón de la Sagra, 3, 28935 Móstoles, Madrid, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Jana
authors.affiliation: Photoactivated Processes Unit, IMDEA Energy Institute, Móstoles Technology Park, Avenida Ramón de la Sagra, 3, 28935 Móstoles, Madrid, Spain. fernando.fresno@imdea.org victor.delapenya@imdea.org.
authors.forename: P
authors.initials: P
authors.lastname: Reñones
authors.affiliation: Thermochemical Processes Unit, IMDEA Energy Institute, Móstoles Technology Park, Avenida Ramón de la Sagra, 3, 28935 Móstoles, Madrid, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Coronado
authors.affiliation: Thermochemical Processes Unit, IMDEA Energy Institute, Móstoles Technology Park, Avenida Ramón de la Sagra, 3, 28935 Móstoles, Madrid, Spain and Chemical and Environmental Engineering Group, ESCET, Rey Juan Carlos University, c/Tulipán s/n, 28933 Móstoles, Madrid, Spain.
authors.forename: D P
authors.initials: DP
authors.lastname: Serrano
authors.affiliation: Photoactivated Processes Unit, IMDEA Energy Institute, Móstoles Technology Park, Avenida Ramón de la Sagra, 3, 28935 Móstoles, Madrid, Spain. fernando.fresno@imdea.org victor.delapenya@imdea.org.
authors.forename: V A
authors.initials: VA
authors.lastname: de la Peña O'Shea
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D046529:Microscopy, Electron, Transmission; D009556:Niobium / Q000737:chemistry*; D010084:Oxidation-Reduction / Q000528:radiation effects; D010087:Oxides / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013059:Spectrum Analysis, Raman; D013635:Tantalum / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014961:X-Ray Diffraction
chemical_list: D017610:Calcium Compounds; D010087:Oxides; C559961:sodium niobate; D009556:Niobium; C404416:sodium tantalate; C059910:perovskite; D002245:Carbon Dioxide; D013635:Tantalum; D012964:Sodium; D014025:Titanium