A novel composition of Al/NaBH4 mixture activated by La and COCl2 in water for hydrogen generation was investigated. The composition had good stability at 298 K with high La content and low COCl2 content, but presented good hydrogen generation performance with increasing global temperature. For example, The Al-15 wt.%La-5 wt.%CoC12/NaBH4 mixture （mass ratio of l：l）yielded 1664 ml hydrogen/1 g mixture with 100% efficiency within 60 min at 333 K. The hydrogen generation rate and amount could be regulated by changing composition design, hydrolytic conditions, etc. There existed a synergistic effect of La and COCl2. Increasing La content was helpful to de- crease crystal size of the mixture, but its hydrolysis byproduct La（OH）3 deposited on Al surface and had side effect on Al hydrolysis. In- creased COCl2 content was attributed to the producing of more actively catalytic sites CO2B/Al（OH）3 formed in the hydrolytic process. Co2B had dual catalytic effect on AlfNaBH4 hydrolysis. It deposited on Al surface and acted as a cathode of a micro galvanic cell. CO2B/Al（OH）3 was also a good promoter to NaBH4 hydrolysis. Therefore, the Al/NaBH4mixture activated by La and COCl2 may be applied as hydrogen generation material and the experimental data lays a foundation for designing practical hydrogen generators.
Well-ordered TiO 2 nanotube arrays (TNAs) were fabricated by electrochemical anodization in a mixed organic electrolyte consisting of ethylene glycol and glycerol. The morphology, structure, crystalline phase, and photocatalytic properties of TNAs were characterized by using TEM, SEM, XRD and photodegradation of methylene blue. It was found that the morphology and structure of TNAs could be significantly influenced by the anodization time and applied voltage. The obtained tube length was found to be proportional to anodization time, and the calculated growth rate of nanotubes was 0.6 m/h. The microstructure analysis demonstrated that the diameter and thickness of the nanotubes increased with the increase of anodization voltage. The growth mechanism of TNAs was also proposed according to the observed relationship between current density and time during anodization. As expected, the obtained TNAs showed a higher photocatalytic activity than the commercial TiO 2 P25 nanoparticles.
WANG ChaoCHEN DaPING GuangXingLIU ShuHUANG XiaNiHUANG YueXiangSHU KangYingLI JingHong
