title: Hybrid Graphene/Titania Nanocomposite: Interface Charge Transfer, Hole Doping, and Sensitization for Visible Light Response.
abstract: We demonstrated for the first time by large-scale ab initio calculations that a graphene/titania interface in the ground electronic state forms a charge-transfer complex due to the large difference of work functions between graphene and titania, leading to substantial hole doping in graphene. Interestingly, electrons in the upper valence band can be directly excited from graphene to the conduction band, that is, the 3d orbitals of titania, under visible light irradiation. This should yield well-separated electron-hole pairs, with potentially high photocatalytic or photovoltaic performance in hybrid graphene and titania nanocomposites. Experimental wavelength-dependent photocurrent generation of the graphene/titania photoanode demonstrated noticeable visible light response and evidently verified our ab initio prediction.
authors: Aijun
authors: A
authors: Du
authors: ‡ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Sciences and Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
authors: Yun Hau
authors: YH
authors: Ng
authors: ‡ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Sciences and Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
authors: Nicholas J
authors: NJ
authors: Bell
authors: Zhonghua
authors: Z
authors: Zhu
authors: ‡ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Sciences and Engineering, University of New South Wales, Sydney, NSW 2052, Australia.
authors: Rose
authors: R
authors: Amal
authors: Sean C
authors: SC
authors: Smith
keywords: charge transfer; first-principle modeling; graphene; hole doping; interface; titania; visible light response