Research Progress on Ammonia Sensors Based on Ti₃C₂T_x MXene at Room Temperature: A Review

Ammonia (NH₃) potentially harms human health, the ecosystem, industrial and agricultural production, and other fields. Therefore, the detection of NH₃ has broad prospects and important significance. Ti₃C₂T_x is a common MXene material that is great for detecting NH₃ at room temperature because it has a two-dimensional layered structure, a large specific surface area, is easy to functionalize on the surface, is sensitive to gases at room temperature, and is very selective for NH₃. This review provides a detailed description of the preparation process as well as recent advances in the development of gas-sensing materials based on Ti₃C₂T_x MXene for room-temperature NH₃ detection. It also analyzes the advantages and disadvantages of various preparation and synthesis methods for Ti₃C₂T_x MXene's performance. Since the gas-sensitive performance of pure Ti₃C₂T_x MXene regarding NH₃ can be further improved, this review discusses additional composite materials, including metal oxides, conductive polymers, and two-dimensional materials that can be used to improve the sensitivity of pure Ti₃C₂T_x MXene to NH₃. Furthermore, the present state of research on the NH₃ sensitivity mechanism of Ti₃C₂T_x MXene-based sensors is summarized in this study. Finally, this paper analyzes the challenges and future prospects of Ti₃C₂T_x MXene-based gas-sensitive materials for room-temperature NH₃ detection.