The replacement of electro-thermal material in heaters with lighter and easy-to-process materials has been extensively studied. In this study, we demonstrate that laser-induced graphene (LIG) patterns could be a good candidate for the electro-thermal pad. We fabricated LIG heaters with various thermal patterns on the commercial polyimide films according to laser scanning speed using an ultraviolet pulsed laser. We adopted laser direct writing (LDW) to irradiate on the substrates with computer-aided 2D CAD circuit data under ambient conditions. Our highly conductive and flexible heater was investigated by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, X-ray diffraction, and Brunauer-Emmett-Teller. The influence of laser scanning speed was evaluated for electrical properties, thermal performance, and durability. Our LIG heater showed promising characteristics such as high porosity, light weight, and small thickness. Furthermore, they demonstrated a rapid response time, reaching equilibrium in less than 3 s, and achieved temperatures up to 190 °C using relatively low DC voltages of approximately 10 V. Our LIG heater can be utilized for human wearable thermal pads and ice protection for industrial applications.
Keywords: flexible; heater; laser-induced graphene; polyimide.