The structure and hydriding/dehydriding behaviors ofLa2Mgl7-10 wt.%Ni composite prepared by mechanical milling were investigated. Compared with the tin-milled sample, the as-milled alloys were ready to be activated an...The structure and hydriding/dehydriding behaviors ofLa2Mgl7-10 wt.%Ni composite prepared by mechanical milling were investigated. Compared with the tin-milled sample, the as-milled alloys were ready to be activated and the kinetics of hydrogen ab- sorption was relatively fast even at environmental temperature. The composite milled for 10 h absorbed 3.16 wt.% hydrogen within 100 s at 290 K. The kinetic mechanisms ofhydriding/dehydriding reactions were analyzed by using a new model. The results showed that hydrogenation processes for all composites were controlled by hydrogen diffusion and the minimum activation energy was 15.3 kJ/mol H2 for the composite milled for 10 h. Mechanical milling changed the dehydriding reaction rate-controlling step from surface penetration to diffusion and reduced the activation energy from 204.6 to 87.4 kJ/mol H2. The optimum milled duration was 5 h for desorption in our trials.展开更多
The Ti0.9Zr0.1V0.2Ni1.5La0.5 alloy samples were synthesized by melt-spinning technique at the different wheel velocity （cooling rate）, and the structure and electrochenfical hydrogen storage properties were investig...The Ti0.9Zr0.1V0.2Ni1.5La0.5 alloy samples were synthesized by melt-spinning technique at the different wheel velocity （cooling rate）, and the structure and electrochenfical hydrogen storage properties were investigated. The result indicated that the structure of the melt-spun ribbons mainly contains C14 Laves phase and V-based solid solution phase. The discharge capacity, cyclic stability, high-rate discharge ability and electrochemical kinetic of the alloy electrodes are correlated with the cooling rate （wheel velocity）, and the maximum discharge capacity is over 200 mA.h/g at the wheel velocity of 20 m/s.展开更多
基金Project supported by the Guizhou Nomarch Fund Project of Excellent Technology and Education Talents (201019)Specialties Projects funded for the Scientific Research Condition of Guizhou High-Level Talents (TZJF200927)
文摘The structure and hydriding/dehydriding behaviors ofLa2Mgl7-10 wt.%Ni composite prepared by mechanical milling were investigated. Compared with the tin-milled sample, the as-milled alloys were ready to be activated and the kinetics of hydrogen ab- sorption was relatively fast even at environmental temperature. The composite milled for 10 h absorbed 3.16 wt.% hydrogen within 100 s at 290 K. The kinetic mechanisms ofhydriding/dehydriding reactions were analyzed by using a new model. The results showed that hydrogenation processes for all composites were controlled by hydrogen diffusion and the minimum activation energy was 15.3 kJ/mol H2 for the composite milled for 10 h. Mechanical milling changed the dehydriding reaction rate-controlling step from surface penetration to diffusion and reduced the activation energy from 204.6 to 87.4 kJ/mol H2. The optimum milled duration was 5 h for desorption in our trials.
基金Acknowledgements This work was supported by the Key Laboratory of Preparation and Applications of Environmental Friendly Materials （Ministry of Education） and the Foundation for Innovative Research Groups of the National Natural Science Foundation of China （Grant No. 20921002）.
文摘The Ti0.9Zr0.1V0.2Ni1.5La0.5 alloy samples were synthesized by melt-spinning technique at the different wheel velocity （cooling rate）, and the structure and electrochenfical hydrogen storage properties were investigated. The result indicated that the structure of the melt-spun ribbons mainly contains C14 Laves phase and V-based solid solution phase. The discharge capacity, cyclic stability, high-rate discharge ability and electrochemical kinetic of the alloy electrodes are correlated with the cooling rate （wheel velocity）, and the maximum discharge capacity is over 200 mA.h/g at the wheel velocity of 20 m/s.
