锂原子修饰硼原子链团簇的结构和储氢性能研究

The structures and hydrogen storage properties of lithium decorated on the end of the boron atomic chain clusters

采用密度泛函方法对锂原子修饰线型硼原子链团簇Li_2B_n(n=2~8)的结构及其储氢性能进行理论研究.结果显示,Li原子可键合于硼链团簇的两端,氢能以分子形式吸附在Li原子周围,每一个Li原子最多可吸附4个氢分子,氢分子的平均吸附能为2.020~2.832 kcal.mol^(-1).其中Li原子修饰B2小团簇的质量储氢分数最大,为31.24 wt%,表明在常温常压条件下它有可能成为一种潜在的储氢媒介.

The structures and the hydrogen storage properties of the linear boron atomic chainsclusters and the lithium decorated boron atomic chains clusters are investigated by using the density functional theory.The results show that the lithium atoms can be decorated on the end of the boron atomic chains clusters but do not suffer from clustering.Every Li atom can adsorb up to four intact hydrogen molecules for the Li-decorated on the end of the boron atomic chains Li2Bn（ n = 2～8） clusters.And the hydrogen average adsorption energy is in the range of 2.020 2.832 kcal.mol-1for the Li2Bn·m H2（ n = 2 8; m = 2～8） clusters.The calculated gravimetric density of hydrogen of Li-decorated on the end of the B2 chain cluster is 31.24 wt%,which shows that the Li-decorated on the end of the boron atomic chains is an optimal choice for hydrogen recycling at the normal temperature and pressure ambient conditions.