Laser-induced graphene integrated into structural composites for manufacturing-to-service multifunctional monitoring

Polymer matrix composites are widely used as structural load-bearing components but lack intrinsic sensing capability. Conventional monitoring strategies rely on extrinsic sensors that often compromise structural integrity and are limited to specific lifecycle stages. Here, we present a multifunctional strategy by embedding electrically independent laser-induced graphene paper (LIGP) functional layers within composite laminates for manufacturing-to-service multifunctional monitoring. By tuning laser scanning parameters and applying plasma surface activation, the LIGP layers with adjustable electrical conductivity and Seebeck coefficient are obtained. During manufacturing, the LIGP monitoring layer provides stage-resolved electrical responses for monitoring temperature-, pressure-, and curing-related responses without additional embedded sensors. In addition, a dedicated LIGP heater layer enables low-energy in-situ Joule heating to assist curing without compromising mechanical performance. Once integrated, the LIGP-based functional system continuously monitors loading conditions and enables active responses such as Joule heating, de-icing, and moisture sensing, demonstrating a transition from passive monitoring to active response. This work provides a feasible strategy for scalable, function–structure integrated smart composites.