A circular approach to reduce, recover and recycle graphene-based printed electronics

The shift towards renewable materials and circular processes is crucial for sustainable printed electronics. Conventional conductive inks rely on petrochemical-based solvents and synthetic binders that hinder recyclability and recovery of high-value materials. Here, we report a recyclable graphene ink formulated with a bio-renewable terpene solvent and cellulose-based binder for electrochemical sensing applications. Using Hansen Solubility as ink formulation framework along the GlaxoSmithKline Solvent Sustainability Guide, we propose linalool as a low-toxicity dispersant alongside the ethyl cellulose binder to enable efficient graphene recovery. We fabricated fully printed electrochemical sensors for physiologically relevant analytes, including ascorbic and uric acid. The devices were subsequently disassembled, enabling recovery of the solvent, substrate, and over 93% of the graphene. Reclaimed materials were reused to fabricate sensors and heaters, with graphene recycled five times without compromising performance. The ink reduces global warming potential by up to 42% compared with conventional graphene inks and by over 59% after recycling, demonstrating a circular approach to sustainable graphene-based printed electronics.