<scp>Low‐Temperature</scp> Total Oxidation of Methane by Pore‐ and Vacancy‐engineered <scp>NiO</scp> Catalysts

Designing methane combustion catalysts operated under low temperature (<400oC) remains a huge challenge, especially for noble-metal-free catalytic systems. With NaCl as a crystalline scaffold, NiO catalyst with abundant oxygen vacancies and an ultra-high specific surface area of 181 m2 g-1 is obtained. The mesoporous NiO exhibits outstanding CH4 combustion performance (T90=370oC at the WHSV= 20,000 ml g-1 h-1). XPS, H2-TPR, kinetic measurements and O18 isotope-labeling experiments together disclose the key role of surface lattice oxygen and reaction mechanism by NiO catalysts. More importantly, the excellent stability of NiO by doping La was obtained (low-temperature thermal stability: 385oC, 400 h, 4 vol.% H2O).