Research on Chemical Looping Combustion-Type Methane Sensor Based on ZnO-SnO2 Nanofibers

ZnO-SnO2 composite nanofibers of methane sensor were prepared by the double jets electrospinning method. A new chemical looping combustion type methane sensor was designed with ZnO-SnO2 composite nanofibers deposited onto Pt thermistor surface as catalytic thin film. The crystalline phase and microstructure of ZnO-SnO2 composite nanofibers were displayed using X-ray diffraction (XRD) and scanning electron microscope (SEM), and the chemical looping combustion reaction and electrochemical characteristic about methane and catalytic thin film were analyzed by CH4 temperature programmed reduction (CH4-TPR) and X-ray photoelectron spectroscopy (XPS). These characteristic tests of the methane sensor were carried out on the traits of sensitive performance, dynamic response, temperature, humidity, selective and stability by DL07-YJ108D type voltage measuring instrument. The conclusion demonstrated that methane sensor based on Zn50 composite nanofibers functioned as catalytic film. When the operating temperature was 350 degrees C and methane concentration was increased from 0. 1 to 60 mu g/L, the linearity and sensitivity of methane sensor were 99. 4% and 0. 12 V/(mu g/L) respectively. Its high response was 8. 2 V, and the dynamic response time and recover time of methane sensor were 5. 4 and 10. 8 s, respectively, with a high relatively humidity level of 95%. The response value of methane sensor was only decreased about 2. 0% when it was continually applied in mine about 6 months.