SiO2@MnO x @Na2WO4@SiO2 core-shell-derived catalyst for oxidative coupling of methane.

SiO2@MnO x @Na2WO4@SiO2 core-shell catalysts were prepared and their fabrication was confirmed using transmission electron microscopy. The formation of Mn-based nanosheets on the silica spheres is important for the deposition of nanoscopic Na2WO4. The SiO2@MnO x @Na2WO4@SiO2 core-shell catalysts were used for the oxidative coupling of methane at a temperature of 700-800 °C at which the nanostructures were completely destroyed. Although the core-shell structures did not survive the high-temperature oxidative coupling of methane, the selective production of olefins and paraffins can be attributed to highly dispersed Na2WO4 derived from confined core-shell structures.