GRAPHERGIA Poster: In-situ laser reduction of graphene oxide on textiles: from lab-scale optimization to roll-to-roll manufacturing

Methodology Laser-assisted graphene reduction on textile objectives In-situ laser reduction of graphene oxide on textiles: from lab-scale optimization to roll-to-roll manufacturing Natalia Kantouni,1,2* Chrysanthi Paparouni3, Despoina I. Batsouli,3 and Spyros N. Yannopoulos 1,2* 1 Foundation for Research and Technology – Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE–HT), GR-26504, Rio-Patras, Greece 2 Department of Chemistry, University of Patras, GR-26504, Rio-Patras, Greece 3Adamant Composites Ltd., Aghias Lavras and Stadiou St., GR-26504, Rio-Patras, Greece * Correspondence at: [email protected] & [email protected] •To establish an eco-friendly laser-assisted method for in-situ graphene deposition onto flexible substrates. •Investigation of the effect of varying GO loadings on the conductivity of the laser irradiated samples. •Comprehensive characterization of the graphene embedded textiles employing Raman Spectroscopy, Scanning Electron Microscopy and Sheet Resistance measurements to assess the structural, morphological and electrical changes of the prepared samples, in respect to different laser power treatments. •Extend the study to diverse textile substrates and utilize an Nd:YAG laser of the roll-to-roll pilot line, to further assess the scalability and versatility of the proposed manufacturing procedure. Background Upscaling to a Roll-to-Roll (R2R) process 21.6 W Laserassisted synthesis of reduced Graphene Oxide (GO) Methodology References Conductivity optimization: Influence of the laser power PLACEHOLDER IMAGE •The integration of graphene into textiles is a vital component for developing next-generation wearable electronics, energy storage, and smart fabrics. •The laser-assisted method for graphene oxide reduction is considered a green and versatile technique to acquire graphene-like structures with high quality and enhanced conductivity. •The ease of fabrication, cost efficiency and environmental sustainability of this method, aligns perfectly with the needs of the market. Offering a great alternative to traditional synthesis routes, that lack on the scalability aspect. Fig. 4: (a) Image of the prepreg textile with LrGO spots, Raman spectra of the LrGO produced by diverse laser energies on (b) prepreg, (c) polyester and (d) polyamide textile substrates. Fig. 3: (a) Image of the R2R pilot line (ADA), LrGO spots employing 4,6 and 8 J on (b) PA and (c)PES textiles. Fig. 2: (a) Representative Raman spectra of the LrGO, produced by different laser powers (red: 18 W and orange: 23.1W) (b) Sheet resistance versus loading plot of the various samples. Fig. 1: SEM images of the bare GO and the LrGO coated textiles, laser treated with powers of 21.6 and 36 W respectively. Table 1 : Comparison of recent literature Rs values with our work. •An airbrush method was used to uniformly coat GO on polyester (PES) ,polyamide (PA) and prepreg textiles. •A fiber-optic-coupled Nd:YAG laser integrated within an R2R pilot line (ADA) was utilized to produce LrGO at large scale. •A simple spraying and a brushing method were employed to evenly coat the graphene oxide dispersion on a thin polyester textile substrate. •Followingly, various samples with GO loadings ranging from 0.5 to 3.1 mg cm-2 were prepared to evaluate the effect of loading on the conductivity of the laser irradiated samples. Material Rs (Ohm sq-1) Ref. GO on Nylon/spandex 87.6 ± 36.2 1 GO on Nylon filtration membrane 51 ± 2 2 GO on Cellulose Acetate membrane 58 ± 3 2 GO on Cellulose Acetate membrane Nitrocellulose 620 ± 40 2 GO on PET/textile 45 3 GO on PES (loading 1 mg cm-2)8.1 ± 0.8 Our work 1 Lipovka, A. et al. Textile Electronics with Laser-Induced Graphene/Polymer Hybrid Fibers. ACS Appl. Mater. Interfaces 15, 38946–38955 (2023). 2 Bonando, M. G. et al. The impact of different flexible substrates on the photothermal reduction quality of graphene oxide. Nanoscale Adv.6, 4604–4610 (2024). 3 Fatkullin, M. et al. Smart Graphene Textiles for Biopotential Monitoring: Laser-Tailored Electrochemical Property Enhancement. ACS Sens. 9, 1809–1819 (2024). Effect of GO loading on conductivity Laser Power (W) Sheet resistance (Ohm sq-1) 18 52.1 ± 1.3 21.6 35 ±0.7 25.2 13.8 ± 1.0 28.8 10.1 ±0.1 32.4 9.9 ±0.4 36 12.3 ± 3.5 39.6 10.7 ± 2.6 43.2 18.1 ±1.0 Table 2: Rs values in respect to the laser power employed to reduce GO films on PES. (a) (b) (a) (b) 8 J 8 J 6 J 6 J 4 J 4 J (c) (d) Raman Spectroscopy •All GO coatings were successfully reduced, independent of the substrate employed. •In all cases, high quality graphene material with high crystallinity was acquired. •Among all energies, the 6 J value seems to provide the the best reduction across all samples. •A CO2 (10.6 μm) industrial type laser was employed to irradiate and reduce the GO coating. •The produced materials were thoroughly characterized to identify the optimum loading and laser conditions to attain the lowest sheet resistance (Rs). (a) (b) (c) 1400 1750 2100 2450 2800 Raman intensity (a.u.) Raman shift (cm-1) LrGO/ PES Raman Spectrometer Four Point Probe for Sheet Resistance measurements GO/PES untreated Treated region