Binary CoOx–SiO₂ Porous Nanostructures for Catalytic CO Oxidation

Via integrative chemistry, the first CoOx–SiO2(HIPE) self-standing monoliths of cobalt nano-oxides embedded within silica macro–mesocellular hosts have been prepared. These binary CoOx–SiO2 porous nanostructure (MUB-100(x)) materials present an average 95% porosity. We found out that high concentration maintains hexagonal-2D organization mesoscopic voids when applying thermal treatment at 700 °C. Their specific surface areas fall between 400 and 500 m2 g–1 assessed by Ar physisorption measurements. At microscopic length scale, as revealed through magnetic investigations, low content foams MUB-100(1) MUB-100(2) are made amorphous β-Co(OH)2 phase coexisting with network, whereas increasing during one-pot syntheses (MUB-100(3) MUB-(4) materials) favors formation spinel Co3O4 olivine Co2SiO4 crystalline nanoparticles silica. When considering CO oxidation catalytic performance, MUB-100(4) is able to totally convert flow before 200 °C (starting 125 °C) while achieving 50% conversion for a light-off temperature (T50) 145 °C, revealing good efficiency in which up 4 cycles performed without disrupting drastically performance reaching thermodynamic stability from cycle 2 4.