Spectroscopic Characterization of Graphene Oxide Fractions: A Preliminary Step Towards Fabric Functionalization

Flexible electronic textiles hold potential applications across various fields, yet current functionalization methods frequently suffer from poor coating uniformity and severe aesthetic alteration. This study addresses these challenges by establishing a multi-analytical approach, based on Raman spectroscopy together with DLS, Zeta potential and XPS measurements, to optimize graphene oxide (GO) precursor selection prior to electrostatic deposition onto cotton fabrics using a polyethyleneimine linker. This coating strategy was inspired by layer-by-layer deposition technique and centrifugation was used to partition a heterogeneous commercial GO precursor into three distinct homogeneous fractions. Raman spectroscopy revealed that centrifugation acts not merely separating GO based on its size but effectively sorts GO sheets based on their chemical functionalization degree. Consequently, this approach allows for the identification of the optimal precursor fraction, balancing sheet dimensions with defect density, to ensure strong functionalization. Overall, this work established a foundational spectroscopic methodology for precursor selection, deposition monitoring and process optimization, which can also be extended to the characterizing and comparison of different commercial GO batches from different industrial suppliers. Finally, micro-Raman mapping and XPS were preliminary applied to verify the textile fiber functionalization.