Sustainable wood electronics by iron-catalyzed laser-induced graphitization for large-scale applications

Abstract

Ecologically friendly wood electronics will help alleviating the shortcomings of state-of-art cellulose-based “green electronics”. Here we introduce iron-catalyzed laser-induced graphitization (IC-LIG) as an innovative approach for engraving large-scale electrically conductive structures on wood with very high quality and efficiency, overcoming the limitations of conventional LIG including high ablation, thermal damages, need for multiple lasing steps, use of fire retardants and inert atmospheres. An aqueous bio-based coating, inspired by historical iron-gall ink, protects wood from laser ablation and thermal damage while promoting efficient graphitization and smoothening substrate irregularities. Large-scale (100 cm2), highly conductive (≥2500 S m−1) and homogeneous surface areas are engraved single-step in ambient atmosphere with a conventional CO2 laser, even on very thin (∼450 µm) wood veneers. We demonstrate the validity of our approach by turning wood into highly durable strain sensors, flexible electrodes, capacitive touch panels and an electroluminescent LIG-based device.

Water Peel-Off Transfer of Electronically Enhanced, Paper-Based Laser-Induced Graphene for Wearable Electronics

“…For transferred LIG patterns using the same condition, a mean conductivity of 19.3 S·cm –1 was reached. Comparing these metrics with other LIG forms, this paper-based LIG reaches the best conductivity levels reported for PI (25–34 S·cm –1 ), wood (23.3 S·cm –1 ), and other engineered lignocellulosic precursors (28 S·cm –1 ), while far exceeding previous reports for paper-based LIG, as evidenced in Figure S5. Considering the porosity of paper, effective conductivity values that consider the fibrous architectures of paper can be estimated.…”

Sustainability in Wood Products: A New Perspective for Handling Natural Diversity

“…Electrically conductive wood materials have great relevance for developing embedded systems of controls and actuators in smart buildings. − A breakthrough in this direction has been recently described by the introduction of iron-catalyzed laser-induced graphitization (IC-LIG), an innovative approach for developing electrically conductive wood surfaces . This approach takes advantage of the intumescent properties of tannic acid coupled with the thermocatalytic graphitization properties of iron ions.…”

“…317−319 A breakthrough in this direction has been recently described by the introduction of iron-catalyzed laser-induced graphitization (IC-LIG), an innovative approach for developing electrically conductive wood surfaces. 320 This approach takes advantage of the intumescent properties of tannic acid coupled with the thermocatalytic graphitization properties of iron ions. A supramolecular iron−tannic acid complex, inspired by the iron-gall ink used for writing since medieval times, is formulated as an aqueous suspension, which after being coated on a wood surface is converted into LIG with a conventional CO 2 laser in ambient atmosphere.…”

Ultrafast materials synthesis and manufacturing techniques for emerging energy and environmental applications

“…A particular advantage of laser-assisted techniques is their high spatial and temporal resolution, allowing precise and controllable fabrication of nanomaterials and nanostructures in desired applications. [67][68][69][70][71][72] (3) Microwave: microwave-assisted methods (Fig. 2c) utilize high-frequency electromagnetic radiation (e.g., microwave) as an energy source and convert it into heat rapidly, which turns precursors into desired products.…”