Sn sites enable efficient water dissociation for aqueous C–C Coupling to bio-jet fuel precursors

A MgAlSnO spinel oxide catalyst with exceptional water tolerance was developed for efficient aqueous-phase C–C coupling of biomass-derived molecules. • The electronic environment of Sn was precisely regulated by calcination temperature, enabling controllable modulation of its p-band center. • In situ DRIFTS revealed that water dissociation is a critical elementary step governing catalytic performance under high water content. • A linear correlation between catalytic activity and the Sn p-band center was established, identifying it as an effective descriptor for water dissociation. • DFT calculations demonstrated that Sn 5p–O 2p orbital hybridization dominates the adsorption and dissociation of water on Sn-based oxides. The development of heterogeneous catalysts for aqueous C–C coupling offers a more promising solution for converting biomass-derived molecules into sustainable bio-jet fuel. This study systematically investigated catalytic activity of layered double hydroxide-derived oxides for furfural (FF) aqueous C–C coupling. MgAlSnO-600 catalyst exhibited superior water tolerance, achieving 95% conversion of furfural (FF) under high-water-content conditions and demonstrating broad substrate generality. In situ DRIFTS and water contact angle measurements reveal that efficient H 2 O dissociation, rather than suppressed water adsorption, is the key factor enabling high catalytic activity under water-rich conditions. Density functional theory (DFT) calculations reveal that the strength of p-p orbital hybridization between Sn 5p and O 2p (H 2 O) orbitals governs the water dissociation rate and determines the catalytic performance. Furthermore, the high linear correlation of the Sn p-band center with both the water dissociation rate and catalytic activity establishes it as a reliable descriptor. This study establishes a scalable heterogeneous catalyst framework enabling the conversion of furfural to fuel precursors in aqueous systems, paving a new pathway for aqueous C–C coupling. The dissociation of H 2 O at Sn sites enables the catalyst to achieve excellent water-poisoning resistance and efficient aqueous-phase C-C coupling. Download: Download high-res image (135KB) Download: Download full-size image