High Concentration of Ti₃C₂T MXene in Organic Solvent

MXenes are currently one of the most widely studied two-dimensional materials due to their properties. However, obtaining highly dispersed MXene materials in organic solvent remains a significant challenge for current research. Here, we have developed a method called the tuned microenvironment method (TMM) to prepare a highly concentrated Ti₃C₂T organic solvent dispersion by tuning the microenvironment of Ti₃C₂T. The as-proposed TMM is a simple and efficient approach, as Ti₃C₂T can be dispersed in N,N-dimethylformamide and other solvents by stirring and shaking for a short time, without the need for a sonication step. The delaminated single-layer MXene yield can reach 90% or greater, and a large-scale synthesis has also been demonstrated with TMM by delaminating 30 g of multilayer Ti₃C₂T raw powder in a one-pot synthesis. The synthesized Ti₃C₂T nanosheets dispersed in an organic solvent possess a clean surface, uniform thickness, and large size. The Ti₃C₂T dispersed in an organic solvent exhibits excellent oxidation resistance even under aerobic conditions at room temperature. Through the experimental investigation, the successful preparation of a highly concentrated Ti₃C₂T organic solvent dispersion via TMM can be attributed to the following factors: (1) the intercalation of the cation can lead to the change in the hydrophobicity and surface functionalization of the material; (2) proper solvent properties are required in order to disperse MXene nanosheets well. To demonstrate the applicability of the highly concentrated Ti₃C₂T organic solvent dispersion, a composite fiber with excellent electrical conductivity is prepared via the wet-spinning of a Ti₃C₂T (dispersed in DMF) and polyacrylonitrile mixture. Finally, various types of MXenes, such as Nb₂CT, Nb₄C₃T, and Mo₂Ti₂C₃T, can also be prepared as highly concentrated MXene organic solvent dispersions via TMM, which proves the universality of this method. Thus, it is expected that this work demonstrates promising potential in the research of the MXene material family.