Hybrid Doping of Few-Layer Graphene via a Combination of Intercalation and Surface Doping

Abstract
Surface molecular doping of graphene has been shown to modify its work function and increase its conductivity. However, the associated shifts in work function and increases in carrier concentration are highly coupled and limited by the surface coverage of dopant molecules on graphene. Here we show that few-layer graphene (FLG) can be doped using a hybrid approach, effectively combining surface doping by larger (metal-)organic molecules, while smaller molecules, such as Br2 and FeCl3, intercalate into the bulk. Intercalation tunes the carrier concentration more effectively, whereas surface doping of intercalated FLG can be used to tune its work function without reducing the carrier mobility. This multi-modal doping approach yields a very high carrier density and tunable work function for FLG, demonstrating a new versatile platform for fabricating graphene-based contacts for electronic, optoelectronic and photovoltaic applications.

Citation
Mansour AE, Kirmani AR, Barlow S, Marder SR, Amassian A (2017) Hybrid Doping of Few-Layer Graphene via a Combination of Intercalation and Surface Doping. ACS Applied Materials & Interfaces. Available: http://dx.doi.org/10.1021/acsami.7b02886.

Acknowledgements
The authors acknowledge Dr. Marcel Said for the early discussion of the hybrid doping approach, Dr. Yadong Zhang for synthesis of the Mo dopant, and Mrs. Lubna Jamshaid for her logistical support. This work was supported by King Abdullah University of Science and Technology (KAUST), and Department of the Navy, Office of Naval Research Award No. N00014-14-1-0126.

Publisher
American Chemical Society (ACS)

Journal
ACS Applied Materials & Interfaces

DOI
10.1021/acsami.7b02886

PubMed ID
28535037

Additional Links
http://pubs.acs.org/doi/abs/10.1021/acsami.7b02886

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