Sustainable lignin “photoresist” for laser-engraved graphene on commercial fabrics

Textile electronics have attracted great interest in wearable technology, yet their facile and reliable fabrication remains challenging. Laser-engraved graphene (LEG) technique enables customizable fabrication of circuits on substrates, but most fabrics cannot sustain high-energy laser exposure. In this study, we develop a fully biomass-based aqueous “photoresist” for LEG by employing lignin, a natural polymer from industrial byproducts, thus enables the facile fabrication of textile electronics on various commercial fabrics. The lignin “photoresist” can be applied onto the targeted fabrics and be converted into high-quality graphene under laser exposure without damaging the fabrics. The obtained graphene exhibits a resistance of 9.18 Ω/sq and is highly suitable for textile electronics. To demonstrate the wide potential of this technique, we fabricated a series of fabric-based sensors, including heavy metal ion sensors, pulse sensors, electrocardiogram electrodes, and flexible batteries. This research provides a versatile, sustainable and eco-friendly approach for the fabrication and integration of electronics on common fabrics and clothes, contributing to the development of practical textile electronics.