Fischer–Tropsch synthesis (FTS) for the production of gasoline and middle distillates in the range of C5–C22 hydrocarbons was investigated using ZSM5-modified Co/SiO2 FTS catalysts. The Co/SiO2 catalyst was prepared by an impregnation method using a cobalt nitrate precursor in a slurry of SiO2, and theh ZSM5-modified Co/SiO2 catalyst was subsequently prepared by synthesizing ZSM5 (Si/Al ratio = 40) by in situ hydrothermal synthesis over the Co/SiO2 catalyst at different ZSM5/(Co/SiO2) weight ratios. The catalytic performance was largely altered by changing acidity and reducibility of cobalt oxides on ZSM5-modified Co/SiO2 catalysts due to the different extents of migration of cobalt oxides from SiO2 to the ZSM5 surface with different degrees of catalytic olefin cracking reaction. The ZSM5-modified Co/SiO2 catalyst with 25 wt %ZSM5 shows a maximum selectivity to C5–C22 hydrocarbons with a high CO conversion due to the smaller cobalt crystallite size possessing a high reducibility and optimum acid site density. The superior catalytic performance on the ZSM5-modified Co/SiO2 catalysts is mainly attributed to the modification of the Co/SiO2 surface with the presence of adjacent ZSM5 particles and the possible migration of cobalt species from SiO2 to the ZSM5 surface during the hydrothermal synthesis of ZSM5.

The combined steam and CO 2 reforming reaction of CH 4 was investigated using LaSrNiO x mixed oxides supported on Al 2 O 3 -modified β-SiC to elucidate the largely enhanced CO 2 conversion at an optimal concentration of Al 2 O 3 modifier. The dispersion of Al 2 O 3 on the SiC support simultaneously altered the dispersion of LaSrNiO x crystallites increasing their strength when combined with the Al 2 O 3 -modified SiC. Although all tested catalysts showed similar activation energies, the increased Al 2 O 3 dispersion on SiC at around 10 wt % Al 2 O 3 modifier was well-correlated with the increased dispersion of active perovskite-like La 2 NiO 4 crystallites which resulted in an enhanced catalytic activity. The formation of smaller NiO and La 2 NiO 4 crystallites through an intimate contact with Al 2 O 3 particles seems to be responsible for the suppressed aggregation of nickel crystallites during higher temperature reforming reactions. The higher amounts of CO 2 adsorption on the well-dispersed basic lanthanum and strontium oxides contained in the LaSrNiO x mixed oxides are also responsible for the enhanced CO 2 conversion. Observed surface properties including the crystallite size of active components, the reducibility of NiO, and the CO 2 adsorption property are explained in terms of the results obtained from X-ray diffraction, X-ray photoelectron spectroscopy, temperatureprogrammed reduction, CO 2 temperature-programmed desorption (CO 2 -TPD), and NH 3 -TPD analyses.

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A cobalt phthalocyanine having an electron‐poor CoN4 (+δ) in its phthalocyanine moiety was presented as an electrocatalyst for hydrogen peroxide oxidation reaction (HPOR). We suggested that hydrogen peroxide as an electrolysis medium for hydrogen production and therefore as a hydrogen carrier, demonstrating that the electrocatalyst guaranteed high hydrogen production rate by hydrogen peroxide splitting. The electron deficiency of cobalt allows CoN4 to have the highly HPOR‐active monovalent oxidation state and facilitates HPOR at small overpotentials range around the onset potential. The strong interaction between the electron‐deficient cobalt and oxygen of peroxide adsorbates in Co─OOH− encourages an axially coordinated cobalt oxo complex (O═CoN4) to form, the O═CoN4 facilitating the HPOR efficiently at high overpotentials. Low‐voltage oxygen evolution reaction guaranteeing low‐voltage hydrogen production is successfully demonstrated in the presence of the metal–oxo complex having electron‐deficient CoN4. Hydrogen production by 391 mA cm−2 at 1 V and 870 mA cm−2 at 1.5 V is obtained. Also, the techno‐economic benefit of hydrogen peroxide as a hydrogen carrier is evaluated by comparing hydrogen peroxide with other hydrogen carriers such as ammonia and liquid organic hydrogen carriers.