Computational Insights into the Hydrodeoxygenation of Phenolic Compounds over Pt–Fe Catalysts

Abstract

Density functional theory calculations were performed to study the adsorption and hydrodeoxygenation (HDO) of phenol, o-cresol, and guaiacol on Pt−Fe surfaces. The crucial impact of bimetallic Pt−Fe surface structures on the catalytic activity and selectivity was revealed. Key parameters in dictating the C Ar −O bond cleavage activity across different phenolic reactants were identified. The phenolic hydroxyl group interacted with surface metal atoms to modify the C Ar −O bond length and charges transferred from the catalyst surface to the related groups of phenolic reactants, thereby influencing the C Ar −O bond cleavage properties. The dehydroxylation reactions of o-cresol proceeded more easily on 1Pt sub −Fe(211), while the C Ar −O cleavage reaction of phenol was more likely to occur on 1Pt ads − Fe( 211). Based on the three possible paths of guaiacol conversion, phenol would be the major product on both the 1Pt ads −Fe(211) and 1Pt sub −Fe(211) surfaces, but its formation was from different pathways. Introduction of Pt in different forms leads to dissimilar structural and electronic effects on the adsorption as well as the HDO activity and selectivity.

Selective Hydrodeoxygenation of Phenol Driven by Synergistic Effects of Dual-Metal Atoms Over C2N Monolayer

“…The E a of the second H-step is 0.84, 1.02, 0.04, 0.06, 1.02, and 0.18 eV for CoCo-, FeFe-, FeMo-, MoMo-, FeNi-, and RuFe-C 2 N, respectively. Agreeing with previous studies, ,,,, the RDS along the DDO pathway is the first direct deoxygenation elementary step or the last H-step. As shown in Figure b, the RDS is the direct deoxygenation process (the first elementary step) on MoMo-, RuFe-, FeMo-, FeNi-, and CoCo-C 2 N, and the last H-step of converting C 6 H 5 * to C 6 H 6 * on FeFe-C 2 N, respectively.…”