Workshop

Laser-Induced Graphene (LIG) technology, initially developed for the fabrication of miniaturized sensors, has recently gained traction in broader applications, expanding beyond small-scale devices to include larger structures such as antennas. This evolution paves the way for the development of complete functional systems for the Internet of Things (IoT), where the intrinsic properties of LIG enable a more sustainable and eco-friendly approach to wireless connectivity.

The photothermal synthesis and patterning of laser-induced graphene from aromatic polymers, through digital fabrication frameworks enabled by Direct Laser Writing, established the grounds for high prototyping and efficient fabrication of carbon-based circuits and electrodes. However, novel nature-derived lignocellulosic and polysaccharide-based materials are increasingly performing as highly effective LIG precursors, through improvements in their formulation and rational control of laser irradiation protocols, boosting graphitization potential and yielding highly conductive graphitic structures of interest. In this presentation, we showcase recent advances on the synthesis of laser-induced graphene from such precursors, including paper substrates, cork and custom-made polysaccharide films, focusing on precursor preparation, compatible laser processing parameters and irradiation outcomes. 

Laser Induced Graphene (LIG) is a three-dimensional porous conductive carbon material created through the laser-induced pyrolysis of polymer precursors. Recently, it has been utilized in soft and wearable electronics, as well as energy storage devices, among other applications.1–3 LIG tracks are produced in a single synthesis/patterning step using laser scribing with an IR or UV laser on polymer precursors. Additionally, biologically-derived precursors are being explored and utilized.4,5 LIG technology provides a maskless and chemical-free alternative to conventional printing methods, opening up unique possibilities for embedding circuits on a wide range of surfaces. In our LAMPSE group, we investigate LIG for developing soft sensors and actuators, and their use in various Robotics and Bioengineering applications. Stretchable conductive composites are produced by incorporating LIG into elastomeric matrices. 

Laser-induced graphene (LIG) can be considered as disruptive technology for creating devices that received much attention in the field of flexible electronics. Among all, energy storage, catalysis, sensing, and separation are the main applications that have been investigated in recent years with large improvements in the respective device performance. Miniaturized supercapacitor - usually called micro-supercapacitor (µSC) - is the most investigated field in which LIG can strongly provide outstanding results concerning the state-of-the-art simplification of the fabrication procedure of the device. However, many open points still limit the possible full exploitation of this technology in the energy storage sector.

Conventional electronics today form on the planar surfaces of brittle wafer substrates and are not compatible with 3D deformable surfaces. As a result, stretchable electronic devices have been developed for continuous health monitoring. Practical applications of the next-generation stretchable electronics hinge on the integration of stretchable sustained power supplies with highly sensitive on-skin sensors and wireless transmission modules. This talk presents the challenges, design strategies, and novel fabrication processes behind a potential standalone stretchable device platform that integrates with 3D curvilinear dynamically changing surfaces. The resulting device platform creates application opportunities in fundamental biomedical research, disease diagnostic confirmation, healthy aging, human-machine interface, and smart Internet of Things.

The increasing number of electronic devices in the Internet-of-Things poses serious concerns about their long-term sustainability. Laser-Induced Graphene is an emerging material whose versatility, ease of fabrication and biocompatibility align well with the next-generation metal-free wireless sensors and antennas. 

The development of cost-effective electrochemical sensors has advanced significantly through innovative manufacturing techniques like laser-induced carbonization and 3D printing, which offer lower fabrication costs and faster production. Our research aims to enhance the sustainability and accessibility of sensor production while maintaining high electrochemical performance. One key method involves using CO₂ laser-induced carbonization to fabricate electrodes by carbonizing non-conductive substrates in a single step. 

Laser-induced graphene (LIG) is fabricated by direct laser writing, which is a low-cost and time effective technique, with a wide range of available precursors including biodegradable, biocompatible and eco-friendly materials. The optimization of the main patterning parameters-power and scan speed-was key to achieve the LIG from polyimide with the best structural morphology, graphitization degree, and electrochemical performance, achieving a supercapacitor with a capacitance of 22.2 mF/cm2 at 0.05 mA/cm2.