Flexible and robust laser-induced graphene heaters photothermally scribed on bare polyimide substrates

• Published in: Carbon (New York) Vol. 144; pp. 116 - 126
• Main Authors: Bobinger, Marco R., Romero, Francisco J., Salinas-Castillo, Alfonso, Becherer, Markus, Lugli, Paolo, Morales, Diego P., Rodríguez, Noel, Rivadeneyra, Almudena
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 01.04.2019; Elsevier BV
• Subjects: Biocompatibility; Carbon; Chemical properties; CNC laser; Electrical properties; Flexible; Graphene; Graphene film heater; Laser ablation; Laser-induced graphene; Mechanical properties; Micro-hotplate; Morphology; New technology; Numerical analysis; Numerical controls; Operating temperature; Organic chemistry; Photomasks; Polyimide; Robustness (mathematics); Semiconductor lasers; Substrates; Temperature; Polyimide; CNC laser; Flexible; Laser-induced graphene; Micro-hotplate; Laser ablation; Graphene film heater
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2018.12.010

We demonstrate the feasibility of fabricating cost-effective and robust laser-induced graphene (LIG) flexible heaters with an innovative technique based on the photothermal production of graphene with a foam-like morphology. The produced devices are precisely defined on a bare polyimide substrate without the need of photomasks by employing a computer numerical control (CNC) driven laser diode. The electrical properties of the LIG-based heaters can be tailored by adjusting the laser power. The resulting conductive material exhibits electrical and chemical properties which are similar to the ones for graphene such as a negative temperature coefficient of −0.46 m°C−1 and a maximum operating temperature of around 400 °C. The developed heaters can outperform the existing emerging technologies showing a very rapid and stable response up to 225 °C with the extra features of flexibility, biocompatibility, and environmental friendliness. In this study, we present a novel CNC-based technique for fabricating laser induced graphene films on bare polyimide substrate. The conductive films are used for flexible thin-film heaters that show a high mechanical and thermal robustness. [Display omitted]