The H2 chemisorption was also performed in Micromeritics 3 Flex analyzer using a U-type cell. The catalyst precursors (~100 mg) were loaded into a cell plugged by quartz wool and reduced in situ. The reduction procedure was the same as the one used for the synthesis of catalysts (see Table ). After reduction, the samples were evacuated under the reduction temperature for 30 min. A leak test was performed after cooling down to 35°C. The absorbed H2 quantity was measured at 0-450 mmHg (absolute pressure) at 35°C. The data was analyzed by a dual-Langmuir model, which assumed the adsorption consist of only strong adsorption (chemisorption) and weak adsorption (physisorption) (Eq. 1):