Solid solution of Ce1-xYxO2-δ supported nickel-based catalysts for auto-thermal reforming of acetic acid with high resistance to coking.

Nickel-based catalysts are widely applied in auto-thermal reforming (ATR) of acetic acid (HAc) to extract hydrogen, but the persistent issue of coking is still a concern. Herein, Ce 1-x Y x O 2-δ solid solutions were obtained to support nickel and the catalytic activity for the ATR was examined. The results indicated that with Y species in CeO 2 lattice, the Ce 1-x Y x O 2-δ solid solution structures with lattice defects and cell dislocation were formed; Meanwhile, the strong nickel-support interaction effectively constrained aggregation of Ni⁰; In addition, the solid solution induced formation of oxygen vacancies, and facilitated transfer and activation of oxygen species (O*). The DFT analysis further evidences the lower formation energy of oxygen vacancy over the solid solution. Therefore, the optimized Ni 0.8 Ce 1.76 Y 0.35 O 4.85 ±δ catalyst provided excellent stability for activity test (50 h), in which HAc conversion and H 2 yield stabilized at 100% and 2.6 mol-H 2 /mol-HAc, respectively, without obvious coking. [Display omitted] • Solid solution Ce 1-x Y x O 2-δ nickel-based catalysts were synthesized by sol-gel. • Lattice defects and cell dislocation were caused by Y atom insertion. • Y doping enhanced resistance to carbon deposition of nickel-based catalyst. • Ni 0.8 Ce 1.76 Y 0.35 O 4.85 ±δ catalyst shows better performance for ATR of acetic acid. • DFT shows that Y doping decreases the formation energy of oxygen vacancy. [ABSTRACT FROM AUTHOR]