Improved synthesis of highly ordered Co-MCM-41

Transition metal incorporated MCM-41 materials were synthesized by careful control of multiple factors affecting the final product quality. Among them, the pH adjustment of the initial synthesis solution of Co-MCM-41 was crucial for the distribution of metallic ions in the silica framework. Higher pH significantly improved the physical structure of Co-MCM-41 and is accompanied by higher porosity. Each pore of Co-MCM-41, at the optimum pH, exhibited a hexagonal pore shaped entrance, not just the usual hexagonal array of pores of approximate circular shape. A mild acid treatment of Co-MCM-41 was a useful technique to remove surface metal oxide, which causes lowering of reduction stability by hydrogen spillover on the surface.