Li-coated B_(36)N_(24) as potential hydrogen storage material

摘要

Using density functional theory, we investigate hydrogen adsorption on Li-coated B_(36)N_(24) clusters. It is found that the preferred binding sites for Li atoms are the hexagonal B_4N_2 and pentagonal B_3N_2 rings. The interaction of Li atoms with the cluster is stronger than that among Li atoms. The clustering of Li atoms is avoided. The coated Li atoms are positively charged and the H_2 molecules are polarized when they approach the Li atoms. Each Li atom in the Li-coated B_(36)N_(24) complexes can adsorb two H_2 molecules. The average adsorption energies are in the range of -0.08 to -0.16 eV/H_2. The fully coated B_(36)N_(24)Li24 can hold up to 48 H_2 with an average adsorption energy of -0.09 eV/H_2, corresponding to a hydrogen uptake of 9.7 wt%.