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We systematically investigate the structural, electronic and magnetic properties, bonding analysis, as well as surface morphology of transition metal monoxides (FeO, CoO and NiO) utilizing density functional theory (DFT) with various functionals across from GGA to GGA+U and hybrid functional. Our results reveal that the screened hybrid functional (HSE) could give a reasonable description on structural and electronic properties of these strongly correlated systems when compared to experiments. Local approximation GGA functional fails to yield the accuracy band gaps. GGA+U approximation are rational when given a reasonable U, but the U which reproduce a reasonable band gap often yield a significant error in describing other properties such as lattice constant or magnetic moment. The computed Crystal Orbital Overlap Population (COOP) indicates that cubic FeO and CoO are metastable phase, while the distortion occurs to enhance stability. Based on the reliable functional, the surface morphology of FeO, CoO and NiO are predicted using Wulff construction approach.

SiO2 is generally regarded as an “inert” support of gold catalysts for CO oxidation. We find that silica obtained from a natural clay mineral can be used as excellent gold-support for efficient CO oxidation at relatively low temperature. Fine Au particles are found to locate around the Al sites, rather than on pure SiO2 area. Accordingly, high Au loading and catalytic activity for the clay-based SiO2 supports are ascribed to the residual aluminum originally from the clay.

Monolithic mesoporous carbons were prepared through a simple autoclaving method using citric acid as catalyst instead of HCl. The presence of citric acid plays an important role in determining the structural ordering of the resultant mesoporous structure due to the –COOH groups which can enhance hydrogen interaction between structural directing agent of triblock copolymer F127 and polymeric carbon precursor of resorcinol–formaldehyde resins. The obtained carbons have a hexagonal pore system, uniform pore size of ∼5.0 nm and high BET surface area of ∼758 m2/g. The prepared mesoporous carbons were used as catalyst for dehydrogenation of propane, exhibiting high catalytic activity and stability. After 50 h time-on-stream, the propane conversion of 12.1% was observed with propylene selectivity of 95.1% in the direct dehydrogenation process, while the propane conversion of 20.1% with propylene selectivity of 25.8% in oxidative dehydrogenation process. It has been found that the surface basic groups are active sites.