Biogenic or green-reduced graphene derivatives have emerged and found applications across diverse domains, including the detection of volatile organic compounds, biomedical uses, stretchable electronics, energy storage, photodetectors, high-contrast displays, and optoelectronic and photochemical technologies. These also encompass areas such as the degradation of waterborne pollutants and electrochemical systems like supercapacitors, lithium-ion storage devices, and various sensing applications. The synthesis of graphene and its derivatives (usually graphene oxide (GO)) frequently involves expensive and hazardous chemicals, posing risks to both the environment and human health. However, advancements in polymer composite research have increasingly fostered interdisciplinary collaboration among scientists, steering the field toward more sustainable practices. Previous empirical studies point out that the rising cost of synthesis is becoming an unavoidable factor in the design of new synthetic methodologies, although cost data is often scarce. One approach for the reduction of expenses is to streamline and optimize the synthesis process, such as by simplifying synthetic routes. The suitability of activity-based cost data for low-cost synthesis decisions, specifically for reduced graphene oxide (rGO), was assessed. Common methods involved complex, multistep procedures with cumbersome preparation phases. First, the synthesis is optimized by introducing guarana as a greener reducing agent. To further analyze cost and green considerations, the number of steps in the process was reduced from eight to three, resulting in time and cost savings. The most remarkable aspect of this new synthetic route is its simultaneous application of green chemistry principles and activity-based costing, which improves both the yield and sustainability of the key steps. Economically, compared to the common method costing 248.64 €/g (with eight steps), this streamlined approach cost 19.48 €/g (with three steps), mainly due to reductions in chemical and energy usage.
Gkika et al. (2025) studied this question.