Laser-induced graphene composite adhesive tape with electro-photo-thermal heating and antimicrobial capabilities

Abstract

Laser-induced graphene (LIG) and its composites have been demonstrated to be useful in broad-reaching applications such as water and air filtration and sensors. A main advantage of LIG is the embedding of conformal graphene foam in any design into polymeric substrates. However, embedded LIG must be detached from the substrate for a composite nanomaterial, and delamination of LIG has been demonstrated. Here, we incorporated LIG as a composite into a double-sided tape using pressure-sensitive adhesives and delamination from the substrate, and demonstrated its use for electro-photo-thermal applications, including bacterial inactivation. LIG was transferred onto thermally conductive pressure-sensitive adhesive containing carbon black, and a double-sided sticky tape was prepared by sandwiching perforated tissue adhesive between two LIG layers, giving enhanced electrical conductivity in the x, y, and z directions compared to commercial carbon tape. The LIG composite tape showed excellent electrothermal properties with a maximum temperature >120 °C at 10 V and a temperature rise >70 °C under 120 mW/cm2 solar irradiation. The same electrothermal activity was observed after 50 heating and cooling cycles and reached a temperature of ∼111 °C. Bacterial inactivation was observed on the surface of the LIG composite tape at ∼3.5 V, and electro- and photothermal effects caused sterilization of the surfaces up to 99.99%. These electrically conductive LIG composite adhesive tapes might be used in electronic applications for heating surfaces at low voltages (<9 V) or to prevent surface biofilm or microbial growth.