MXene Nanosheet/Cerium Oxide Microsphere-Based Sensitive Methane Gas Sensor for an Online Safety Valve Leakage Monitoring System

Methane is one of the primary components of natural gas and gas and is also the principal constituent of coal mine gas. In order to construct a high-performance methane gas sensor, the Ti 3 C 2 T x MXene nanosheets and CeO 2 nanospheres were prepared by etching and hydrothermal methods as sensing materials. The detection ability of the Ti 3 C 2 T x /CeO 2 composite was compared with that of the single Ti 3 C 2 T x sensor toward methane gas sensing. The sensing performance of the Ti 3 C 2 T x /CeO 2 composite was greatly enhanced and showed better sensitivity and higher humidity resistance than that of a single Ti 3 C 2 T x sensor. According to the characterization and experimental results, the property enhancement of the Ti 3 C 2 T x /CeO 2 composite sensor is significantly due to the modification of CeO 2, the high carrier mobility of Ti 3 C 2 T x, and the synergistic effect of the combination of the two nanomaterials. Based on the Ti 3 C 2 T x /CeO 2 composite sensor, a valve state detection system was constructed and achieved real-time monitoring of methane leakage from safety valves during the transportation process and runtime safety estimation for methane gas.