Interfacial Self-Assembly of Ti₃C₂T_x MXene Thin Films and Their Electrochromic Properties

The 2D layered nanostructure of Ti 3 C 2 T x boasts excellent electrical conductivity and a substantial specific surface area. The pseudocapacitive behavior of Ti 3 C 2 T x in acidic solutions ensures that Ti 3 C 2 T x films can rapidly undergo redox reactions, leading to reversible changes in light absorption and thereby achieving color changes. In this article, we employed a simple, operable interfacial self-assembly method with mild preparation conditions to fabricate Ti 3 C 2 T x electrochromic films. By modulation of the solvent system and the dosage of the Ti 3 C 2 T x dispersion during the self-assembly process, highly ordered and uniformly dense Ti 3 C 2 T x films were successfully prepared. The results showed that the self-assembled Ti 3 C 2 T x films had a transmittance modulation range of 23.23%, a coloring time of 7.76 s, a bleaching time of 7.88 s, and a cycling stability of 98.16% after 800 s of switching. The Ti 3 C 2 T x films can achieve rapid and reversible color changes from deep blue to dark green, demonstrating excellent cycling stability and superior electrochromic performance. It proves the feasibility of applying Ti 3 C 2 T x materials in the field of electrochromism. Moreover, the rich surface active site and tunability of Ti 3 C 2 T x offer more possibilities for optimizing the performance of electrochromic materials.