Design of a Low-Cost Electrochemical Reactor System for Graphene Oxide Production

Graphene oxide (GO) production via electrochemical exfoliation has attracted a lot of attention because it is a green, safe, and efficient technique with good quality and greater scalability compared to the conventional synthesis routes. In this study, we present the development of a low-cost (ca. US$50), automated electrochemical reactor for the GO synthesis via electrochemical exfoliation of graphite. The system is based on an Arduino-controlled reactor capable of modulating key synthesis parameters, including voltage levels, duration, and the number of cycles, enabling precise process control. A 24-1 factorial design was employed to investigate the influence of process variables-particularly the electrolyte concentration, voltage magnitude, electrolysis time, and number of voltage cycles-on the structural, morphological, and colloidal properties of GO. The results demonstrate that optimizing the electrolyte concentration and the reaction time flakes with uniform size distribution (11.38 ± 0.48 μm) were obtained. Increasing the number of cycles enhances exfoliation efficiency, yielding larger (ca. 35 μm) and thinner (3-6 nm) flakes with higher oxidation degrees and improved colloidal stability, as evidenced by zeta potential measurements reaching -49 mV. Temperature monitoring revealed that the cycling strategy helps lower the reaction temperature by 5 ºC, which promotes more controlled oxidation and exfoliation of graphite. This work highlights a versatile and scalable approach to GO production with tunable properties, offering an environmentally friendly and reproducible alternative to conventional chemical oxidation methods.