Effects of the substrate on graphone magnetism: A density functional theory study

Highlights: • A DFT study of the adhesion of graphone to quartz and copper is presented. • The magnetization of graphone adsorbed on copper is reduced by four times. • In the case of adsorption on quartz, the magnetization is halved. • The electron pairing of unpaired p-electrons plays a key role in quenching. • Even a very small anisotropy can induce ferromagnetism above room temperature. The magnetism of graphone, a single-side-hydrogenated graphene derivative, has been related to the localized and unpaired p-electrons associated with the unhydrogenated carbon atoms. In the present density functional theory study, the effects the adhesion to either Cu(111) or α-quartz (0001) surface on the magnetic properties of graphone have been investigated. The total magnetization of the graphone adsorbed to copper and quartz surface is reduced by four and two times, respectively, with respect to the isolated graphone. We have shown there is electronic charge transfer from surface towards three-fold coordinated C atoms of graphone, but the main role in the partial magnetism quenching is played by bond formation and the consequent electron pairing of p-electrons. The critical temperature has been investigated on the basis of the mean field theory to evaluate the stability of the magnetism at ordinary temperature.