Furfural Adsorption and Hydrogenation at the Oxide‐Metal Interface: Evidence of the Support Influence on the Selectivity of Iridium‐Based Catalysts. Issue 6 (27th January 2022)

• Record Type: Journal Article
• Authors: Campisi, Sebastiano; Motta, Davide; Barlocco, Ilaria; Stones, Rebecca; Chamberlain, Thomas W.; Chutia, Arunabhiram; Dimitratos, Nikolaos; Villa, Alberto
• Is Part Of: ChemCatChem. Volume 14:Issue 6(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-27
• Subjects: biomass -- heterogenous catalysis -- metal-support interactions -- spillover -- supported catalysts; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.202101700
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: Here, tetrakis(hydroxymethyl)phosphonium chloride‐protected colloidal iridium nanoparticles were deposited by sol‐immobilisation on three different supports (CeO2, NiO and TiO2 ) and were investigated for the liquid‐phase direct hydrogenation (H2 atmosphere) and catalytic transfer hydrogenation – CTH (N2 atmosphere) of furfural to study the effect of the H donor. The occurrence of strong‐metal support interactions in 1 wt % Ir/CeO2 catalyst, as disclosed by XPS, was revealed to be responsible for the high activity observed in the direct hydrogenation (81 % conversion after 6 h) and for the unusual selectivity to 2‐methylfuran (70 %) under CTH conditions. On the other hand, Ir/NiO showed peculiar selectivity to tetrahydrofurfuryl alcohol in both H2 and N2 atmospheres (71 % and 70 %, respectively). The density functional theory calculations further showed that the unique selectivity of Ir/NiO may be ascribed to the adsorption properties of furfural on the support, which activates a dual‐site hydrogenation mechanism. Abstract : The catalytic behaviour of Ir nanoparticles in furfural hydrogenation is sensitive to the nature of metal‐support interphase. Metal‐support interactions in Ir/CeO2 catalyst trigger charge transfer phenomena which enhance the activity and selectivity. A dual‐site mechanism is responsible for the unique selectivity of Ir/NiO: furfural is preferentially adsorbed on NiO and therein reduced by hydrogen migrating from Ir surface to the support.