Hydrogen storage on calcium-decorated BC_3 sheet: A first principles study

摘要

Hydrogen storage on the calcium-decorated BC_3 sheet is studied by first principles calculations. We find that the Ca atoms can be strongly adsorbed on the BC_3 sheet without clustering, which facilitates the reversible hydrogen adsorption and desorption. For one Ca atom adsorbing on the (2 × 2) BC_3 unit cell, each Ca could adsorb up to six hydrogen molecules. By adsorbing Ca atoms on both sides of the BC_3 sheet to form a (1 × 1) pattern, a hydrogen capacity up to 8.4 wt % can be achieved, and the average binding energy of hydrogen molecules adsorbed by Ca atoms is about 0.28 eV.