Structural and electronic properties of monolayer hydrogenated honeycomb III–V sheets from first-principles

Using first-principles calculations, we investigate the structural and electronic properties of monolayer hydrogenated honeycomb III–V sheets. The lattice constants and cohesive energies of the hydrogenated III–V (XY H2, X=B, Al, Ga, and Y =N, P, As) sheets depend on the III–V elements and follow the same trend as the atomic radii of the elements. We find that the short lattice constants correspond to the large cohesive energies of the hydrogenated III–V sheets. Similar to the graphane sheet, the hydrogenated BP and BAs sheets prefer the chair conformation. While for the hydrogenated BN, AlN, AlP, and GaN sheets, the boat conformation is favored. For the hydrogenated AlAs, GaP, and GaAs sheets, the chair and boat conformations are degenerate structures. We obtain that all the hydrogenated III–V sheets are wide-gap semiconductors. With GW corrections, the band gaps of hydrogenated III–V sheets follow the order of nitrogen > phosphorous > arsenic compounds for both the chair and boat conformations.