Engineering difference of band structure between mirror symmetrical adsorption and antisymmetrical adsorption of the identical group on a graphene sheet
School of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
Received in final form: 23 February 2019
Accepted: 27 March 2019
Published online: 26 April 2019
Symmetry of adsorption site is the key to control the graphene band gap. When the adsorption sites change from mirror-symmetry adsorption (MSA) to mirror antisymmetric adsorption (MAA) position, the bandgap change (BC) exhibits two opposite tendencies. Therefore, a standard was developed to determine the type of band gap modification of graphene. When BC is negative, the bonding state between the adsorbent and graphene was the dominant factor. When BC is positive, the built-in electric field becomes dominated. Continuous tuning of the band gap can be achieved by adsorbing the appropriate functional groups. Our findings set the standard for determining the type of band gap modification and open the way for controllable adjustment of graphene band gap.
© EDP Sciences, 2019