Gold nanoparticle-based eco-friendly ink for electrode patterning on flexible substrates

Au nanoparticles functionalized by short poly(ethylene glycol) chain ligands were suspended in a hydroalcoholic medium. This suspension was then printed by inkjet onto a Kapton® substrate. Gold electrodes consisting of four stacked printed layers exhibited a conductivity of (1 ± 0.1) × 107 S/m, close to that of Au bulk, after low-temperature thermal annealing. The electrochemical behaviour with respect to heterogeneous electron transfer reactions and the reactivity towards thiol chemisorption are identical to those obtained when a conventional polycrystalline Au electrode is used.