The promoter effect of Nb species on the catalytic performance of Ir-based catalysts for VOCs total oxidation

Chávez-Sifontes, M. ; García, A. ; Sanchis, R. ; Furgeaud, C. ; Mayoral, A. (Universidad de Zaragoza) ; Arenal, R. ; Morgan, D.J. ; Taylor, S.H. ; López, J.M. ; García, T. ; Solsona, B.

Resumen: Ir/TiO2 catalysts promoted by niobium have been synthesized, characterized by different complementary techniques, and tested for the total oxidation of a set of alkanes and their mixtures. The addition of appropriate amounts of niobium to Ir/TiO2 catalysts resulted in a remarkable increase in the catalytic activity compared to the Nb-free Ir/TiO2 catalysts. The promotion caused by the presence of niobium has been related to the massive presence of isolated IrOx surface species which, interestingly, present remarkable reducibility and, consequently, excellent catalytic activity. Conversely, the IrOx species formed in the catalyst in the absence of niobium also include IrO2 clusters with lower intrinsic reactivity. Similarly, Nb-loadings exceeding the theoretical monolayer tends to the formation of bulk Nb2O5 species on the titania surface that provokes the formation of IrO2 nanoclusters. A positive influence on the reactivity of non-stoichiometric surface Ti3+ species that generates oxygen vacancies is also observed.

Idioma: Inglés

DOI: 10.1016/j.jece.2022.108261

Año: 2022

Publicado en: Journal of Environmental Chemical Engineering 10, 5 (2022), 108261 [12 pp.]
ISSN: 2213-3437

Factor impacto JCR: 7.7 (2022)

Categ. JCR: ENGINEERING, ENVIRONMENTAL rank: 12 / 55 = 0.218 (2022) - Q1 - T1
Categ. JCR: ENGINEERING, CHEMICAL rank: 16 / 141 = 0.113 (2022) - Q1 - T1

Factor impacto CITESCORE: 9.5 - Chemical Engineering (Q1) - Environmental Science (Q1)

Factor impacto SCIMAGO: 1.198 - Chemical Engineering (miscellaneous) (Q1) - Waste Management and Disposal (Q1) - Process Chemistry and Technology (Q1) - Pollution (Q1)

Tipo y forma: Article (Published version)

Área (Departamento): Área Física Materia Condensada (Dpto. Física Materia Condensa.)