TITLE:
Effect of NaCl Highly Textured Crystalline Substrates on the Raman Response of Graphene
AUTHORS:
Rafael Antolin-Jimenez, Doroteo Mendoza López
KEYWORDS:
Graphene, Multilayer Graphene, NaCl, Raman Spectroscopy, Optical Contrast, Two-Dimensional Materials, Substrate Effects
JOURNAL NAME:
World Journal of Nano Science and Engineering,
Vol.16 No.3,
September
7,
2026
ABSTRACT: The interaction between graphene and the substrate on which it is supported plays a fundamental role in determining its optical and electronic properties. In this work, multilayer graphene samples were synthesized through mechanical exfoliation and deposited onto conventional Si/SiO2 substrates and NaCl highly textured crystalline substrates. Optical contrast microscopy and Raman spectroscopy were employed to determine the number of graphene layers and to evaluate substrate-induced effects. Unlike graphene on Si/SiO2, graphene deposited on NaCl exhibited negative optical contrast and reduced wavelength dependence. Raman analysis revealed substrate dependent doping behavior: graphene on SiO2 presented predominant p-type doping, whereas graphene on NaCl showed a tendency toward n-type doping with strain contributions dominating the spectral shifts. Carrier concentrations were estimated to be on the order of 1012 cm−2. These results demonstrate the strong influence of ionic crystalline substrates on graphene properties and highlight NaCl as a promising platform for studying electrostatic substrate effects in two-dimensional materials.