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arXiv · 2503.12459

A Universal Raman Spectroscopic Framework for Defect Quantification in Mono-to-Multilayer Graphenic Materials: The Graphene Atlas

Kazunori Fujisawa·Bruno R. Carvalho·Pedro Venezuela·Cheon-Soo Kang·Yoong Ahm Kim·Takuya Hayashi·Mauricio Terrones
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Abstract

Point defects, though atomically small, significantly influence the properties of 2D materials. A general method for characterizing point defect density ($n_{ D }$) in graphenic materials with arbitrary layer number ($n_{ L }$) is currently lacking. Here, we introduce the Graphene Atlas, a non-destructive Raman spectroscopy-based framework for defect quantification in diverse graphenic systems. We demonstrate that the relative fractions of the double-resonance D and 2D Raman bands, which arise from competing scattering processes, exhibit a universal relationship with $n_{ D }$, independent of $n_{ L }$. Plotting Raman data on a plane defined by defect-related and layer number-related parameters enables a direct and quantitative determination of $n_{ D }$ and $n_{ L }$. This Graphene Atlas provides a transformative tool for real-time defect quantification in scalable manufacturing of graphenic materials, bridging fundamental research and industrial applications. This framework establishes a new standard for defect characterization of graphenic systems, facilitating their optimization for advanced technological applications.

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Kazunori Fujisawa, Bruno R. Carvalho, Pedro Venezuela, Cheon-Soo Kang, Yoong Ahm Kim, Takuya Hayashi, Mauricio Terrones. 2025-03-16. A Universal Raman Spectroscopic Framework for Defect Quantification in Mono-to-Multilayer Graphenic Materials: The Graphene Atlas. https://arxiv.org/abs/2503.12459

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