The synergistic role of Nb2O5 in tuning Ni reducibility and acidity to enable efficient aviation fuel production from biomass derivatives

The production of sustainable aviation fuels (SAF) via hydrodeoxygenation (HDO) of biomass-derived aldol-condensation intermediates has attracted extensive attention. In this work, a composite Nb 2 O 5 -γ-Al 2 O 3 supported Ni catalyst was designed to modify Ni reducibility and catalyst acidity for efficient HDO. We found that the formation of Nb-O-Al interfacial bonds effectively suppressed the generation of Ni-O-Al, significantly weakening the strong metal-support interaction (SMSI) inherent to γ-Al 2 O 3 and greatly enhancing the reducibility of Ni. As a result, the Ni 0 fraction increased from 27.01% on Ni/γ-Al 2 O 3 to 47.09% on 15Ni/N2A1. Meanwhile, the strong Lewis acidity associated with Nb 5+ provided crucial sites for C-O bond cleavage, while the intrinsic acidity and mesoporous structure of γ-Al 2 O 3 were preserved and further optimized within the composite support. TEM and CO-pulse measurements confirmed improved metal dispersion and reduced Ni particle size, collectively strengthening both hydrogenation and deoxygenation functions. The composite 15Ni/N2A1 catalyst achieved a high alkane yield of 79.6 wt% with initial reaction rate of 35.90 mmol·L −1 ·h −1 , in the HDO of the furfural-cyclopentanone aldol-condensation product, together with excellent substrate adaptability and cycling stability. Overall, the composite Nb 2 O 5 -γ-Al 2 O 3 enables synergistic regulation of Ni reducibility, medium and strong acidity, providing an effective design strategy for high-performance non-noble metal catalysts in SAF production by HDO.