Band‐Gap Manipulations of Monolayer Graphene by Phenyl Radical Adsorptions: A Density Functional Theory Study. Issue 12 (12th June 2014)

• Record Type: Journal Article
• Authors: Huang, Lin; Sk, Mahasin Alam; Chen, Peng; Lim, Kok Hwa
• Is Part Of: Chemphyschem. Volume 15:Issue 12(2014)
• Page Start: 2610
• Page End: 2617
• Publication Date: 2014-06-12
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201402133
• Languages: English
• ISSNs: 1439-4235

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Phenyl radical (Ph^.) adsorption on monolayer graphene sheets is used to investigate the band‐gap manipulation of graphene through density functional theory. Adsorption of a single Ph^. on graphene breaks the aromatic π‐bond and generates an unpaired electron, which is delocalized to the <italic>ortho</italic> or <italic>para</italic> position. Adsorption of a second radical at the <italic>ortho</italic> or <italic>para</italic> position saturates the radical by electron pairing and results in semiconducting graphene. Adsorption of a second radical at the <italic>ortho</italic> position (<italic>ortho</italic>–<italic>ortho</italic> pairing) is found to be more favorable than adsorption at the <italic>para</italic> position (<italic>ortho</italic>–<italic>para</italic> pairing), and the <italic>ortho</italic>–<italic>ortho</italic> pairing has stronger effects on band‐gap opening compared with <italic>ortho</italic>–<italic>para</italic> pairing. Adsorption of even numbers of Ph^. on graphene by <italic>ortho</italic>–<italic>ortho</italic> and <italic>ortho</italic>–<italic>para</italic> pairings, in general, increases the band gap. Our study shows promise of band‐gap manipulation in monolayer graphene by Ph^. adsorption, leading to potential wider applications of graphene.</p> </abstract>