Innovative approaches to safe and sustainable material synthesis: Optimizing Ti3C2 MXene properties via design of experiments and chemometric analysis

Abstract

MXenes are 2D materials that have received increasing attention since their first synthesis in 2011. They attracted attention due to their unique mechanical, electronic, optical and chemical properties, which make them suitable for multi-sectorial applications. These properties are strictly related to the physico-chemical characteristics of the materials that, in turn, depend on the synthesis conditions. Since some synthesis parameters may be more or less important than others and/or act specifically on a characteristic, in this paper we investigated the impact of the synthesis conditions on the structure and, therefore, the properties of Ti₃C₂T_x MXene, synthetized through the “classic” method, i.e., etching of Ti₃AlC₂ using hydrofluoric acid. We followed an approach combining design of experiment and chemometric analysis; in this way, we could understand and quantify the impact of each synthetic parameter with only 8 experiments. We found that the HF concentration is fundamental for obtaining a complete conversion to MXene. However, higher concentration can be detrimental for the specific capacitance of the materials. This approach is interesting because it allows savings time and costs, entering a logic of Safe and Sustainable by Design (SSbD) that is crucial for such kind of materials.