CNa42+团簇的结构及其储氢性能研究

氢是一种理想的二次能源,它将成为化石燃料最有希望的替代能源之一,也是亟待开发的重要能源。而氢能的储存成本高,危险性大是急需解决的问题。理论上预测CNa_4~(2+)的储氢性能,通过理论分析,发现了每个CNa_4~(2+)团簇最多可与16个H2分子有效结合,获得23.5%的质量储氢密度。在B3LYP理论水平上,H2分子与CNa_4~(2+)团簇的平均相互作用能在2.107～4.948Kcal/mol之间。由于CNa_4~(2+)的质量储氢密度在7.1～23.7wt%之间,符合美国能源部的要求目标(5.5 wt%)。研究结果表明,CNa_4~(2+)在一定环境条件下可逆吸放氢性能良好,可作为潜在的理想高容量储氢材料。

STRUCTURE AND HYDROGEN STORAGE PROPERTIES OF CNa42+ CLUSTER

Hydrogen is an ideal secondary energy, it will become one of the most promising alternatives to fossil fuel, and presses for the development of the important sources of energy. However, the high cost and risk of hydrogen energy storage method is the urgent problems to be solved. Theoretically predict the hydrogen storage properties of CNa₄²⁺ cluster shows that the stable CNa₄²⁺ is a candidate material for hydrogen storage. Within the framework of density functional theory (DFT), it was found that it can bind to 16 H₂ molecules per CNa₄²⁺ cluster with the highest gravimetric hydrogen storage capacity of 23.7 wt%. At the B3LYP theory level, the average interaction energy between H₂ and CNa₄²⁺ clusters is in the range of 2.107~4.948 Kcal/mol. Accord with the requirement of the US department of energy''s goal (5.5 wt%), the research results show that CNa₄²⁺ cluster with the gravimetric hydrogen storage capacity is in the range of 7.1~23.7 wt%. Our results show that CNa₄²⁺ can be used as an ideal high capacity hydrogen storage material under certain environmental conditions.