Effects on structure by spectroscopic investigations, valence state and morphology properties of FeCo-containing SnO2 catalysts for glycerol valorization to cyclic acetals

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2024-09, Vol.317, p.124416, Article 124416
• Main Authors: Martins, Antonio J., de Cássia F. Bezerra, Rita, Saraiva, Gilberto D., Lima Junior, José A., Silva, Rômulo S., Oliveira, Alcineia C., Campos, Adriana F., Morales, Marco A., Jiménez-Jiménez, José, Rodríguez-Castellón, Enrique
• Format: Article
• Language: English
• Subjects: Catalysts; Iron; Nanostructure; Oxides; Spectroscopy; Tin
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2024.124416

[Display omitted] •Structure, valence state and morphological properties of nanostructured Fe-containing SnO2 solids.•Sol-gel, coprecipitation and nanocasted solids in the glycerol valorization to cyclic acetals.•Mössbauer and XPS showed Co and Sn included in the structure of Fe oxide and well-dispersed Fe3+ and Fe2+ surface active sites.•Raman, FTIR and EPR besides morphological features demonstrated structural stability for the sol–gel correlating with the catalytic performance. The effects on the structure, valence state and morphological properties of FeCo-containing SnO2 nanostructured solids were investigated. The physicochemical features were tuned by distinct synthesis routes e.g., sol–gel, coprecipitation and nanocasting, to apply them as catalysts in the glycerol valorization to cyclic acetals. Based on Mössbauer and XPS spectroscopy results, all nanosized FeCoSn solids have Fe-based phases, which contain Co and Sn included in the structure, and well-dispersed Fe3+ and Fe2+ surface active sites. Raman, FTIR and EPR spectroscopies measurements of the spent solids demonstrated structural stability for the sol–gel based solid, which is indeed responsible for the highest catalytic performance, among the nanocasted and coprecipitated counterparts. Morphological and elemental analyses illustrated distinct morphologies and composition on solid surface, depending on the synthesis route. The Fe/Co and Fe/Sn surface ratios are closely related to the catalytic performance. The improved glycerol conversion and selectivities of the solid obtained by sol–gel method was ascribed to the leaching resistance and the Sn action as a structural promoter.