Searching for the sizable atomic-scale magnetism: A comparative study of boron/hydrogen chemisorbed on topological defects in graphene

Recent experiments have identified that both boron (B) and hydrogen (H) atoms might induce atomic-scale magnetism on graphene. Using the first-principles calculations and analyses, we show that B adatom chemisorbed on 48-type topological defects in graphene not only enhances the adsorption energy dramatically, but also significantly induces a sizable atomic-scale spin moment 1.08 μ_B. The underlying mechanism can be attributed to the abundant charge transfer of B adatom and local bonding environment (B/tetragonal ring), facilitating to form B-C covalent bonds. However, such spin polarization does not happen on 558-type defects. In sharp contrast, H adatom can not induce sizable atomic-scale magnetism on either 48- or 558-type defect. We further identity that the moderate kinetic barrier of B adatom along 48-type line defect makes it highly possible to achieve stable antiferromagnetic spin chain. Our findings might provide another feasible host material to realize stable and sizable atomic-scale magnetism of B adatom.