Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2014 Sep 8;15(5):055004.
doi: 10.1088/1468-6996/15/5/055004. eCollection 2014 Oct.

Improving the electrical properties of graphene layers by chemical doping

Muhammad Farooq Khan  1 , Muhammad Zahir Iqbal  1 , Muhammad Waqas Iqbal  1 , Jonghwa Eom  1
Affiliations

Improving the electrical properties of graphene layers by chemical doping

Muhammad Farooq Khan et al. Sci Technol Adv Mater. .

Abstract

Although the electronic properties of graphene layers can be modulated by various doping techniques, most of doping methods cost degradation of structural uniqueness or electrical mobility. It is matter of huge concern to develop a technique to improve the electrical properties of graphene while sustaining its superior properties. Here, we report the modification of electrical properties of single- bi- and trilayer graphene by chemical reaction with potassium nitrate (KNO3) solution. Raman spectroscopy and electrical transport measurements showed the n-doping effect of graphene by KNO3. The effect was most dominant in single layer graphene, and the mobility of single layer graphene was improved by the factor of more than 3. The chemical doping by using KNO3 provides a facile approach to improve the electrical properties of graphene layers sustaining their unique characteristics.

Keywords: Raman spectroscopy; chemical doping; electrical properties; graphene; potassium nitrate.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
(a) Raman Spectrum of SLG. Lorentzian curve fitting of (b) BLG and (c) TLG. (d) Comparative Raman spectra of pristine SLG, BLG and TLG. Insets in a, b and c show SEM images of SLG, BLG and TLG devices.
Figure 2.
Figure 2.
Raman spectra of (a) pristine and KNO3-doped SLG, (c) pristine and KNO3-doped BLG and (e) Pristine and KNO3-doped TLG. (b), (d) and (f) depict the absence of D peak of pristine and KNO3-doped SLG, BLG and TLG, respectively. The colors coding of panels a, c and e are same as panel b, d and f, respectively.
Figure 3.
Figure 3.
(a) Ratios of intensities of SLG, BLG and TLG as function of reactions time. (b) Full width at half maxima (FWHM) of 2D band of Raman Spectra of SLG, BLG and TLG as a function of reaction time.
Figure 4.
Figure 4.
Resistivity as a function of back gate voltage (Vg) for (a) SLG before and after KNO3 treatment for different reaction time, (b) BLG before and after KNO3 treatment for different reaction time and (c) TLG before and after KNO3 treatment for different reaction time.
Figure 5.
Figure 5.
(a) Shift in Dirac point positions of SLG, BLG and TLG devices as a function of reaction time. (b) Change in charge density (Δn) as a function of KNO3 reaction time for SLG, BLG, and TLG. (c) The electron and hole mobility as a function of KNO3 reaction time for SLG, BLG, and TLG.
See this image and copyright information in PMC

References

    1. Novoselov K S, Geim A K, Morozov S V, Jiang D, Zhang Y, Dubonos S V, Grigorieva I V. and Firsov A A. Electric field effect in atomically thin carbon films. Science. 2004;306:666. doi: 10.1126/science.1102896. - DOI - PubMed
    1. Weiss N O, Zhou H L, Liao L, Liu Y, Jiang S, Huang Y. and Duan X F. Graphene: an emerging electronic material. Adv. Mater. 2012;24:5782. doi: 10.1002/adma.201201482. - DOI - PMC - PubMed
    1. Geim A K. and Novoselov K S. The rise of graphene. Nat. Mater. 2007;6:183. doi: 10.1038/nmat1849. - DOI - PubMed
    1. Schedin F, Geim A K, Morozov S V, Hill E W, Blake P, Katsnelson M I. and Novoselov K S. Detection of individual gas molecules adsorbed on graphene. Nat. Mater. 2007;6:652. doi: 10.1038/nmat1967. - DOI - PubMed
    1. Adam S, Hwang E H, Galitski V M. and Das Sarma S. A self-consistent theory for graphene transport. P. Natl. Acad. Sci. USA. 2007;104(18392) doi: 10.1073/pnas.0704772104. - DOI - PMC - PubMed

LinkOut - more resources