Effect of facile nitrogen doping on catalytic performance of NaW/Mn/SiO₂ for oxidative coupling of methane

The oxidative coupling of methane (OCM) has great potential as a cost-effective pathway to directly convert methane to C₂ species such as ethane and ethylene. Although NaW/Mn/SiO₂ is one of the most promising catalysts for OCM, an improvement in its catalytic performance is required to achieve high C₂ yield. Herein, we show that a relatively simple pyridine treatment of NaW/Mn/SiO₂ leads to nitrogen-doping of the active sites, resulting in significantly high CH₄ conversion rate while maintaining high C₂ selectivity. Various characterisation techniques such as X-ray diffraction analysis, X-ray photoelectron spectroscopy, temperature-programmed reduction analysis, transmission electron microscopy, and density functional theory calculations are employed to understand the effect of N doping on the performance of NaW/Mn/SiO₂ for OCM.