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提出了两个稳定的团簇B12Sc4和B12Ti4,基于理论计算,研究了它们的结构与储氢性质.结果发现,在这两个稳定的团簇中,过渡金属原子不会聚合在一起而影响它们对氢气的吸附.B12Sc4最多可以吸附12个氢分子,达到7.25%(质量分数)的储氢量,它的平均每氢分子吸附能量为-10.5kJ·mol-1.B12Ti4最多只能吸附8个氢分子,储氢量为4.78%,但其平均每氢分子吸附能量可达-50.2kJ·mol-1.进一步计算表明,即使在77K,也需要很高的氢气压力才能使12个氢分子都吸附到B12Sc4上.电子结构分析表明,B12Ti4-nH2吸附结构中的Kubas作用要大于相应B12Sc4-nH2结构中的Kubas作用.
Two stable clusters, B12Sc4 and B12Ti4, are proposed, and their structures and hydrogen storage properties are studied based on theoretical calculations. It is found that in these two stable clusters, the transition metal atoms do not polymerize and affect them Hydrogen adsorption.B12Sc4 can absorb up to 12 hydrogen molecules, reaching a hydrogen storage capacity of 7.25% (mass fraction), its average adsorption energy per hydrogen molecule is -10.5kJ · mol-1.B12Ti4 can only adsorb up to 8 Hydrogen molecules, hydrogen storage capacity of 4.78%, but the average energy per hydrogen molecule up to-50.2kJ · mol-1. Further calculations show that, even at 77K, also need a high hydrogen pressure in order to make 12 hydrogen molecules are Adsorbed onto B12Sc4.The electronic structure analysis showed that the Kubas effect in the B12Ti4-nH2 adsorption structure was greater than that in the corresponding B12Sc4-nH2 structure.