• • Oxygen vacancies in metal oxide supports, such as CeO2 and ZrO2, enhance CO2 activation and facilitate carbon removal, reducing carbon deposition by up to 50% at 700°C in Ni-based catalysts.
• • The presence of oxygen vacancies inhibits metal sintering by anchoring active metal particles, maintaining Ni crystallite sizes below 10 nm after 100 h on stream at 800°C.
• • Defect engineering strategies, including doping with Mn or Ce, increase oxygen vacancy concentration, improving catalytic activity (CH4 conversion >80%) and stability (no deactivation over 50 h) in DRM.
• • Advanced characterization techniques (XAFS, XPS) confirm the dynamic nature of oxygen vacancies, which act as active sites for CO2 dissociation, lowering the activation energy by 20 kJ/mol compared to vacancy-free surfaces.