Laser induced graphene on phenolic resin and alcohol composite sheet for flexible electronics applications

Abstract

Harnessing Laser-induced graphene (LIG) on various substrates, its optimization and application for various electronic devices has increased in the recent years. LIG has been reported as an alternative process for the realization of graphene for flexible electronics with excellent strength, conductivity and mechanical robustness. However, in a single-step manufacturing process, the development of a cost-effective, scalable electronic system using LIG is very challenging. In this work, a novel, simple, low-cost, and solid-state approach has been introduced to print and develop LIG-based conductivity traces and patterns. Here, the LIG conductive zones have been formed on various platforms by using phenolic resin (PR). The LIG regions were effectively developed from direct CO2 laser ablation on the PR and polyvinyl alcohol (PR-PVA) composite sheets. This technique makes it possible to easily create highly conductive arrays on various substrates for realizing the components and devices for flexible electronics. By utilizing the augmented power and the speed of CO2 laser, and the ratio of PR-PVA, the optimal conductivity of the formed LIG on PR-PVA sheet has been observed. Unique characteristics of LIG on PR-PVA include simple synthesis process, flexibility, ability to form a thin film with desired conductivity, and cost-effectiveness. The feasibility and viability of the successful LIG on PR-PVA sheet was demonstrated for applications like the capacitive touch sensor and the pressure sensor matrix.