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Reflectance spectroscopic methods the electronic, redox and structural properties of Mn-Na-W/SiO 2 catalysts prepared by the incipient wetness impregnation method and mixture slurry method were studied in detail. Since POSS nanotechnology (POSS = polyhedral oligomeric silsesquioxanes) has attracted attention as tooling for synthesis of catalysts with novel properties and functionalities, we expanded this method for the preparation of Mn-Na-W/SiO 2 catalyst. The physicochemical and catalytic properties of Mn-Na-W/SiO 2 catalysts prepared by conventional methods and POSS nanotechnology were examined comparatively. In all studied Mn-Na-W/SiO 2 catalysts both individual oxides (MnO x , WO 3 ) and bimetal oxide phases (Na 2 WO 4 , MnWO 4 ) are found in addition to oxide particles of high dispersion. The UV-Vis Diffuse Reflectance indicates that Na + cations facilitates stabilization of octahedrally coordinated Mn 3+ Oh cations in the isolated state, while Mn 3+ Oh promote the disordering of W 6+ cations in the supported system. The Mn-Na-W/SiO 2 prepared using metal-POSS precursors marks out presence of unglobular SiO 2 particles, higher dispersion of MnO x and MnWO 4 particles and more easily reducible metal-oxide species. The catalysts prepared by incipient impregnation method and mixture slurry method have practically similar catalytic performance while the catalyst prepared by POSS nanotechnology method shows lower activity and selectivity. At 800вЂ’850 В°C the increase of C 2 hydrocarbons yield from 4 to 15% and the rise of molar ratio РЎ 2 Рќ 4 /C 2 H 6 from 0.2 to 1 are observed when impregnation or mixture slurry method are used for catalyst preparation instead of POSS nanotechnology method.

Effect of Preparation Mode on the Properties of Mn-Na-W/SiO2 Catalysts for Oxidative Coupling of Methane: Conventional Methods vs. POSS Nanotechnology