Synthesis and evaluation of NiO@MCM-41 core–shell nanocomposite in the CO2 reforming of methane

Abstract

In this paper, the synthesis of core shell structured NiO@MCM-41 nanocomposite via vesicles as soft template is reported for the first time. Its catalytic performance was investigated in the CO2 reforming of methane (CRM) conversion. Stable vesicles first formed with CTAB/SDBS surfactant ratio of 1:2. Nickle nitrate was added to the vesicle mixture followed by addition of the aqueous solution of vesicle containing Ni cations inside to the MCM-41 gel. After high-temperature calcination, NiO@MCM-41 nanocomposite were obtained. The structural symmetry and the surface morphology were characterized by transmission electron microscope (TEM), low angle X-Ray Diffraction (XRD) and N2 adsorption/desorption analysis. TEM image confirmed core–shell structure and the hexagonally ordered structure of shell of MCM-41 silica. The results indicated that the average diameter of synthesized core–shell NiO@MCM-41 particles is 70–80 nm and the most of them are of spherical shape. The result of small angle XRD and N2 isotherm adsorption/desorption analyses indicated successfull formation of mesoporous shell. Hydrogen consumption by the catalyst mainly at 700 °C in TPR profile showed the strong interaction of the most of Nickel content with the support. CRM conversion on the prepared catalyst after 245 min of reaction led to H2 conversion at 42%, CO2 conversion at 48% with H2/CO yield ratio of 0.8.