The study of the hydrogen storage capacity of the Ti atoms coated Si@Ga12 clusters

The average binding energy of the Ti atoms to the hollow site on the Si@Ga12 surface and the distance between the neighboring two Ti atoms are 5.20 eV and 2.8 Å, respectively larger than the experimental cohesive energy of bulk Ti and the experimental bond length of the Ti2 dimer, so the clustering of Ti atoms can be prevented, this is critical for large amount hydrogen storage. Ti-Si@Ga12 and Ti2-Si@Ga12 can adsorb 6 and 12H2 molecules separately with the average adsorption energy of 0.37 and 0.30 eV, which is suitable for hydrogen storage under near-ambient conditions. The average desorption temperature analysis and the molecular dynamic simulation explore that the structures reported here are favorable for the reversible hydrogen storage at near-ambient conditions.211