Metal–Insulator Transition and Heterostructure Formation by Glycines Self-Assembled on Defect-Patterned Graphene

• Published in: Journal of physical chemistry. C Vol. 122; no. 26; pp. 14598 - 14605
• Main Authors: Ersan, F, Üzengi Aktürk, O, Aktürk, E, Ciraci, S
• Format: Journal Article
• Language: English
• Published: American Chemical Society 05.07.2018
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.8b03421

This study unveils critical physical and chemical processes taking place at the interface between an amino acid, glycine, and defected graphene. Although glycine interacts weakly through van der Waals attraction with pristine graphene, it can set rather strong bonding at the close proximity of low-coordinated C atoms of single and triple vacancies and also at the edges of nanoribbons. The adsorption of a glycine molecule first leads to a reconstruction of the defect through a concerted process, which in turn induces magnetic metal–nonmagnetic insulator transition. This way, glycine can be pinned at the defect site with well-defined atomic configuration and electronic structure. In particular, libration frequency of the adsorbed glycine is attributed to significant restoring forces, which is essential for the self-assembly of glycines. Organic overlayer produced by self-assembled glycines on defect-patterned graphene constitutes a junction (heterostructure) with bilateral electronic and optical properties and offers novel device functions from biographene interfaces. These predictions are obtained from first-principles calculations using density functional theory.