Probing Electronic Doping in CVD Graphene Crystals Treated by HNO3 Vapors

Nikos Delikoukos; Stavros Katsiaounis; John Parthenios; Labrini Sygellou; Dimitrios Tasis; Konstantinos Papagelis

doi:10.1021/acsomega.4c05697

Probing Electronic Doping in CVD Graphene Crystals Treated by HNO₃ Vapors

ACS Omega. 2024 Nov 22;9(49):48246-48255. doi: 10.1021/acsomega.4c05697. eCollection 2024 Dec 10.

Authors

Nikos Delikoukos^{1

2}, Stavros Katsiaounis¹, John Parthenios¹, Labrini Sygellou¹, Dimitrios Tasis^{3

4}, Konstantinos Papagelis^{1

5}

Affiliations

¹ Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), Stadiou Street, Platani, Patras 26504, Greece.
² Department of Physics, University of Patras, Patras 26504, Greece.
³ Department of Chemistry, University of Ioannina, Ioannina 45110, Greece.
⁴ University Research Center of Ioannina (URCI), Institute of Materials Science and Computing, Ioannina 45110, Greece.
⁵ School of Physics, Department of Solid-State Physics, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.

Abstract

In this work, we present a comprehensive protocol for achieving hole doping in graphene through exposure to nitric acid (HNO₃) vapors. We demonstrate gradual p-type surface doping of CVD-grown graphene on a Si/SiO₂ substrate by thermally depositing nitric acid molecules to form self-assembled charge transfer complexes. Detailed analysis of charge carrier concentration and Fermi energy shifts was conducted using Raman, X-ray and ultraviolet photoelectron spectroscopies (XPS/UPS). Our methodology, including a novel PMMA coating step, ensures stability and efficiency of the doping process, highlighting its effectiveness in inducing permanent hole doping while maintaining the structural integrity of the graphene.