Dual‐site Re/ <scp> In ₂ O ₃ </scp> enables selective hydrodeoxygenation of fatty acids via suppressed decarbonylation

Abstract Selective deoxygenation of fatty acids to diesel‐range alkanes without carbon‐chain shortening is essential for sustainable biomass upgrading, but high selectivity remains challenging by competing decarbonylation/decarboxylation pathways. Here, a Re/In 2 O 3 featuring Re single atoms and ReO 3 clusters was synthesized for the hydrodeoxygenation of stearic acid. In contrast to In 2 O 3 , which primarily yields 1‐octadecanol (93.1% selectivity) with minimal n‐octadecane (1.2% selectivity), the optimized Re/In 2 O 3 catalyst achieves 100% selectivity diesel‐range alkanes (&gt;85% n‐octadecane). Isotopic labeling, in situ spectroscopy, and kinetic analyses reveal Re‐induced synergy: ReO 3 enhance H 2 dissociation, while Re single atoms promote bidentate adsorption of fatty acids, and oxygen vacancies in In 2 O 3 facilitate selective C–O bond cleavage. This multifunctional synergy suppresses C–C bond scission and significantly lowers the apparent activation energy for hydrodeoxygenation by 36.5 kJ·mol −1 . The catalyst exhibits broad applicability across diverse carboxylic acids, including unsaturated and aromatic substrates, underscoring its potential for efficient biomass utilization.