In the present study, two models of atom occupation in LaNi4Co were put forward and corresponding valence electron structures (VESs) of these two models were investigated according to empirical electron theory (EET...In the present study, two models of atom occupation in LaNi4Co were put forward and corresponding valence electron structures (VESs) of these two models were investigated according to empirical electron theory (EET) of solids and molecules. Results demonstrate that the VES-concerned hardness factor (FH) of LaNi4Co is lower than that of LaNi5, so LaNi4Co has lower hardness, higher plasticity and improved anti-pulverization ability. In the mean time, the difference of the equilibrium hydrogen pressure between LaNiaCo and LaNi5 was analyzed in the electronic level. The analysis shows that the strength of the weakest bond net in octahedron lattice interstices of LaNi4Co is much lower than that in LaNis; consequently, LaNi4Co's bond net easily deforms to accommodate hydrogen so that LaNi4Co has lower equilibrium hydrogen pressure in comparison with LaNis. The results can provide some theory guide on the design of hydrogen storage alloys.展开更多
基金financially supported by National Natural Science Foundations of China(Nos.51301149 and 50371059)
文摘In the present study, two models of atom occupation in LaNi4Co were put forward and corresponding valence electron structures (VESs) of these two models were investigated according to empirical electron theory (EET) of solids and molecules. Results demonstrate that the VES-concerned hardness factor (FH) of LaNi4Co is lower than that of LaNi5, so LaNi4Co has lower hardness, higher plasticity and improved anti-pulverization ability. In the mean time, the difference of the equilibrium hydrogen pressure between LaNiaCo and LaNi5 was analyzed in the electronic level. The analysis shows that the strength of the weakest bond net in octahedron lattice interstices of LaNi4Co is much lower than that in LaNis; consequently, LaNi4Co's bond net easily deforms to accommodate hydrogen so that LaNi4Co has lower equilibrium hydrogen pressure in comparison with LaNis. The results can provide some theory guide on the design of hydrogen storage alloys.