Free-Standing Functional Laser-Induced Graphene-PVA Laminates

Laser-induced graphene (LIG) merges the high conductivity of graphenic carbon with direct laser patterning, yet most LIG remains bound to its polymer substrate, limiting its use as thick, transferable electrodes. Thick free-standing LIG is highly sought for powering and warming flexible systems but remains elusive. Here, we present a solvent-free laminate approach that transforms substrate-bound LIG into thickness-tunable, free-standing films through laser-assisted exfoliation, stacking, and hot-press bonding with poly(vinyl alcohol) (PVA). The resulting laminates, 60-180 μm thick, maintain an electrical conductivity of ∼1.1 × 10³ S m^-1 and survive 1500 bending cycles with <1.1% resistance change. For the six-layer laminate (L-6, 180 μm thick), electro-thermal heating attains 151 °C at 2 V with a heating rate of 17 °C s^-1. When the same L-6 laminate is laser-machined into an interdigitated electrode pattern and used as the electrodes for a microsupercapacitor, it delivers an areal capacitance of 12.2 mF cm^-2 at 0.1 mA cm^-2 and 94.7% capacitance retention after 5000 charge-discharge cycles. Because all steps employ commercially available materials and ambient-pressure processing, the method enables scalable fabrication of multifunctional, free-standing LIG electrodes suited to wearable electronics, localized heating, and compact energy-storage devices.