Laser-Induced Graphene Electrodes for Electrochemistry Education and Research

Abstract

Many aspects of electrochemical education, such as electroanalysis demonstrations, require three-electrode-cell experimental setups. Many researchers and educators use screen-printed electrochemical electrodes, which are miniature and disposable but are relatively expensive and use proprietary fabrication components. The present article describes how to laser-scribe complete three-electrode graphene-based electrodes that can compete with (and, in some regards, even rival) commercial screen-printed electrodes. The process of optimization of the lasing procedure to produce laser-induced graphene using almost any laser cutter available to the reader is described. A way to form a Ag/AgCl pseudoreference electrode on the graphene trace to complete the three-electrode cell, without usage of commercial inks or complicated printing technologies, is demonstrated. Electrochemical characterization of the electrode surface, reference electrode stability, and student practice demonstration of analytic applications of the produced cells (determination of dopamine concentration and coffee polyphenols) are described. These experiments and procedures act both as a method of fabrication of laser-scribed electrodes and as an educational material for introduction to electrodeposition, voltammetry, and electroanalysis.