Self-organized NiO architectures: Synthesis and catalytic properties for growth of carbon nanotubes

Flower-shaped NiO architectures have been synthesized successfully through annealing α-Ni(OH)2 precursor, which are obtained on plane alloy substrate by a hydrothermal route. The SEM results show that these structures are composed of porous NiO nanosheets. Hexamethylenetetramine (HMT) was proved to be effective in promoting the self-organization of α-Ni(OH)2 nanosheets into flower-shaped architectures during hydrothermal treatment. The morphology of NiO architectures could be readily changed by adjusting the reaction temperature. The formation processes of these structures were discussed. Furthermore, the as-formed NiO architectures have been used as catalysts for the formation of carbon nanotubes in methane diffusion flame and show good catalytic activity.