碱金属锂原子修饰硅原子链团簇的结构和储氢性能

采用密度泛函理论(DFT)方法研究Li2Sim(m=2,4,6)链状团簇结构及其储氢性能。研究结果表明,氢分子在碱金属Li原子修饰的三种硅链结构中均发生吸附,并且每个Li原子都可以吸附多个氢分子,其中两个Li原子修饰Si2链的结构能够吸附氢分子的储氢质量分数达18.6 wt%,氢分子的平均吸附能为1.850 kcal/moL。结果表明,碱金属Li原子修饰的硅链在室温条件下可作为氢气的存储媒介。

THE STRUCTURES AND HYDROGEN STORAGE PROPERTIES OF ALKALI METAL LITHIUM DECORATED ON THE END OF THE SILICON ATOMIC CHAIN CLUSTERS

The structures and the hydrogen storage properties of the alkali metal lithium decorated the linear silicon atomic chains clusters are investigated by using the density functional theory. The results show that the lithium atoms can decorate on the end of the silicon atomic chain clusters but not suffer from clustering. Every Li atom can absorb up to several intact hydrogen molecules in the Li-decorated silicon atomic chains Li₂Si_m (m=2, 4, 6) clusters. The calculated gravimetric density of hydrogen for Li-decorated the Si₂ chain cluster is up to 18.6 wt%, and the hydrogen average adsorption energy is 1.850 kcal.mol^-1, which shows that the Li-decorated silicon atomic chains can be used as hydrogen storage materials under the room temperature condition.