Bio-inspired conductive ink: Harnessing plant based binder for customizing electrochemical, rheological and printing applications

Abstract

The search for environmentally friendly electronic materials has become more intense in recent years, encouraged by the need to limit the hazards of electronic waste. Conductive inks are crucial in printed electronics. However, challenges like toxic metals, low throughput, and complex fabrication processes hindered their widespread use and spurred the exploration of natural material-based alternatives. This research explores the development of a natural Rosin and Carbon-based Conductive (RoCa) ink, focusing on optimizing the composition and its in-depth electrochemical, rheological, spectroscopic, and morphological characterization. The developed RoCa ink presented shear thinning behavior with a conductivity range between 500 and 1500 S/m and sheet resistance between 14 and 7.82 Ω/sq. The ink coatings were hydrophobic and stable to acid, basic and neutral pHs. The ink was characterized using Raman spectroscopy to understand carbon allotropes and their disordered forms with layers of graphite. FTIR was used to study the functional groups of the ink and XRD and SEM were used to study crystallite size, particle morphology and blending. The customisable electrochemical and mechanical properties of the RoCa ink paved the way towards sustainable and green printing as an environmentally benign alternative to traditional conductive inks in electronic applications.