Design of Ti₃C₂T_x/SnO₂-Selective Ethanolamine Sensor

Two-dimensional transition metal carbides/nitrides (MXenes) show great potential in volatile organic compound (VOC) sensors owing to their exceptional electrical properties, numerous active sites, and abundant terminal functional groups. However, pure MXene Ti 3 C 2 T x is prone to oxidative degradation under ambient environment, and the insufficient response and poor stability are still grand challenges. Hereby, by deliberately introducing metal oxide semiconductor in multilayer Ti 3 C 2 T x, a promising Ti 3 C 2 T x /SnO 2 sensor with excellent long-term stability and outstanding selectivity is developed for VOC monitoring. The research shows that the Ti 3 C 2 T x /SnO 2 hybrid sensor implements efficient detection of hydrogen-bonded gases and is especially highly efficient with ethanolamine (EA). The sensitivity of the hybrid sensor to EA is improved by over 10-fold in comparison with pristine Ti 3 C 2 T x, besides the good selectivity to over 12 different VOCs. The synergistic effects of n-n nanoheterojunctions, the large specific surface area of 45.186 m 2 /g and mesoporous-rich hierarchical structure, and the functional terminal groups together facilitate the EA-sensitive properties. In addition, the innovative preparation of the Ti 3 C 2 T x /SnO 2 sensor, which takes advantage of terpinol, contributes to the close contact of Ti 3 C 2 T x /SnO 2 on the ceramic tubes, thus improving the sensor sensitivity. The scientific findings of this work may provide valuable ideas for the exploration of innovatively composite gas sensors.