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Efficient hydrogen storage, transportation and generation are key-technology for future hydrogen economy. Sodium borohydride (NaBH4) stands out as promising hydrogen energy carrier with merits of high volumetric density and environmentally benign hydrolysis products. Flower-like layered double hydroxide α-Co(OH)2 with intercalation of B species was synthesized via hydrothermal crystallization method using sodium tetraphenylboron as source of B and alkaline, which makes it different from the previous supporting materials. Pure or mixed cobalt oxides with different valence states containing B (CoO/B, Co3O4/B, Co+CoO/B, CoO+Co3O4/B) were subtly prepared via controlling calcination temperature, time and atmosphere for sodium borohydride hydrolysis. Coral-like CoO+Co3O4/B displayed superior hydrogen generation rate (6478 mlH2·min−1·g−1metal) with arrhenius activation energies of 41.14 kJ/mol for NaBH4 hydrolysis in alkaline solutions compared to those reported pure precious metals. The out-standing catalytic performance of CoO+Co3O4/B may be attributed to electron transfer among cobalt oxide. DFT calculation indicates NaBH4 hydrolysis undergoes a reaction path on CoO+Co3O4 surface with lower relative energies.

Carbon deposition, which may reduce the number of active sites or remove metal particles from the catalyst surface, is an urgent issue for the partial oxidation of methane (POM) to synthesis gas. To solve this problem, Ni/ZrO 2 @SiO 2 catalysts were prepared by a modified Stober method. The investigation was focused mainly on the role of ZrO 2 addition and mesopore silica shell in preventing carbon deposition. The structural properties and carbon deposition of catalysts were characterized by XRD, TEM, N 2 adsorption and TG techniques. The oxygen transfer capacity and reducibility of catalysts were evaluated by oxygen storage capacity (OSC) and temperature programmed reduction (TPR). Inspiringly, the Ni/ZrO 2 @SiO 2 catalyst was proved to be more active and possessed less carbon deposition due to the higher reducibility and oxygen storage/release capacity. Importantly, compared with the support catalysts, the catalysts coated by mesopore silica shell showed exceptional resistance to coking, because the edge and corner atoms favor to carbon deposition were selectively blocked by silica shell, in addition, the size of the pore channel prevented growth up of carbon filament.