Performance regulation of acetic acid auto-thermal reforming reaction: Oxygen vacancy defects and active sites controlled by V species

Hydrogen can be produced from acetic acid (HAc) via auto-thermal reforming (ATR). Ni-based catalysts are widely used in ATR of HAc, but suffer from deactivation due to coke deposition, sintering, and oxidation. To address these issues, Ni-Sm-V-O catalysts were prepared via sol-gel method by incorporating vanadium and samarium. Results showed that V incorporation promoted formation of SmVO 3 perovskite, which orchestrated a synergistic promotion mechanism. Specifically, the perovskite structure simultaneously modulated the electronic and geometric properties of the catalyst. On one hand, charge transfer from the V-doped support created electron-rich Ni sites, which enhanced the metallic Ni 0 stability and facilitated the activation of C–H/C–C bonds in acetic acid. On the other hand, the lattice distortion induced abundant oxygen vacancies, which served as activation centers for oxidants (H 2 O/O 2 ). These factors reinforced each other during the reaction: the carbonaceous intermediates generated on the highly dispersed active Ni sites were instantly gasified by the mobile active oxygen species (O ⁎ ) migrating from the adjacent vacancies. This cooperative “cracking-gasification” cycle effectively suppressed coke deposition while maintaining high activity. Notably, no deactivation was observed during the 50-h testing, which is fundamentally attributed to the synergistic suppression of coke deposition via V-induced electronic modulation and oxygen vacancy engineering. This work reveals that constructing the SmVO 3 perovskite effectively addresses the deactivation challenge of Ni-based catalysts, offering robust potential for hydrogen production via the ATR process. • Distorted SmVO 3 supported Ni catalyst was synthesized via sol-gel method. • Oxygen defect engineering in SmVO 3 boosted active oxygen species generation. • Reducibility and dispersion of Ni species were improved over the SmVO 3 support. • High catalytic performance was found for H 2 production via ATR of acetic acid. • Charge transfer and oxygen vacancies within SmVO 3 enable exceptional 50-h stability.