Algorithm for Reproducible Analysis of Semiconducting 2D Nanomaterials Based on UV/VIS Spectroscopy

Abstract

Rapid and reliable analysis of liquid dispersions of 2D materials is essential for fully harnessing their potential, allowing size and quality validation before subsequent processing or device fabrication. Existing UV-VIS extinction spectroscopy-based metrics, particularly those related to thickness, have shown promise but rely on manual data processing, which can introduce irreproducibility and user errors. To address this challenge and enable uniform analysis across laboratories, a freely available program is developed for the reproducible analysis of nanosheet dispersions. Specifically, a smoothing routine is applied to the spectral data, takes the second derivative, and use integral areas to find the wavelength of exciton transitions. This program enables rapid measurement of nanosheet concentration, length, and thickness by UV-VIS spectroscopy and thickness metrics are refined for eight common 2D nanomaterials. The program and methodology are freely available for use and allow metrics for new materials to be implemented easily in the future.

17 pages, 6 figures

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