Ultrafast carrier dynamics in Ti3C2Tx MXene: insights from transientabsorption spectroscopy across the ultraviolet, visible, and near-infrared spectrum

MXene, with their exceptional optical and plasmonic properties, exhibit broad application prospects in the fields of sensors and optoelectronic devices. A deep understanding of the carrier dynamics within these materials is crucial for optimizing the performance and design of these applications. Here, we employ transient absorption spectroscopy to systematically analyze the ultrafast dynamic characteristics of two-dimensional Ti₃C₂T_x MXene across ultraviolet, visible, and near-infrared bands. The experimental results reveal in detail the complex dynamic processes of electrons in MXene materials under photoexcitation, including significant ground state bleaching effects, excited-state absorption phenomena, and absorption changes closely related to surface plasmon resonance. Furthermore, by selecting and analyzing the kinetic curves of these processes, we gain a deeper understanding of the carrier dynamics behavior of MXene materials at different time scales. These findings not only significantly enhance our comprehension of the light absorption mechanisms of MXene materials but also hold extreme value in guiding the innovative applications of highperformance optoelectronic devices based on MXene in key technological fields such as energy conversion and thermal management.