Brief introduction of results
Laser-induced graphene (LIG) is a foamy porous material consisting of several layers of graphene obtained by irradiating various carbon-containing substrates with a laser. The ability to synthesize LIGs from paper and other cellulose-related materials is a surprise, as a variety of potential applications in the form of low-cost, flexible and biodegradable devices open the door. In this paper, researchers such as António J.S. Fernandes and Florinda M. Costa of the University of Aveiro in Portugal published a paper titled "Conversion of paper and xylan into laser-induced graphene for environmentally friendly sensors" in the journal Diam Relat Mater. The study discussed the materials for synthesizing LIG on different types of filter paper and xylan biopolymers. In particular, paper LIG formation by single-step irradiation is reported, providing improvements to traditional multiplex laser methods and explaining the conditions that allow for this simplified synthesis. All relevant process parameters are covered and their impact on the electrical properties, structure and morphology generated is assessed. In addition, LIGs obtained from xylans, a rich and often underutilized biopolymer, were demonstrated for applications for temperature sensing. These results provide a better understanding of what is needed to synthesize highly conductive LIGs from paper and related materials, paving the way for applications in areas ranging from biomonitoring to consumer electronics, while reducing costs and environmental impact.
Illustrated reading
Figure 1. SE-SEM images of laser-induced graphene formed on activated carbon filter paper for different irradiation powers and scanning speeds with a scan line spacing of 0.1 mm.
Figure 3. (ad) Sample photographs obtained after a single scan of the filter paper irradiation (focusing) with scan line spacing of 100 μm, 80 μm, 50 μm and 30 μm, respectively. (e) Representative Raman spectra of PAPER LIG samples in SE-SEM cross-sectional images and (f) (d). (g) Explain how the reduced scan line interval allows LIG to be obtained with a single scan.
Figure 4. SE-SEM images of laser-induced graphene formed on filter paper at a scanning speed of 40 mm s-1, at different irradiation powers and scan line spacing.
Figure 6: (a) Sample photograph obtained by laser irradiation of carboxymethyl xylan film. Raman spectra of the sample in (b) (a), showing the characteristics of laser-induced graphene. (c) SE-SEM images of LIGs obtained from modified xylans. (d) Cross-section SE-SEM image of lig obtained from xylan showing the thickness of LIG. (e) Real-time measurement of the resistance of the conductive path formed by laser irradiation of carboxymethyl xylan films at different temperatures. (f) Magnified view of a scan between 30°C and 35°C
brief summary
This work contributes to a better understanding of the laser-induced graphene synthesis process, complementing the field's precursor substrate arrays and the resulting materials. This encourages future applications in flexible, conductive and environmentally friendly devices.
literature:
https://doi.org/10.1016/j.diamond.2022.108855