Research on Acetylene Sensing Properties and Mechanism of SnO_2 Based Chemical Gas Sensor Decorated with Sm_2O_3

摘要

Acetylene C_2H_2 gas is one of the most important fault characteristic hydrocarbon gases dissolved in oil immersed power transformer oil. This paper reports the successful preparation and characterization of samarium oxide Sm_2O_3 decorated tin oxide SnO_2 based sensors with hierarchical rod structure for C_2H_2 gas detection. Pure and Sm_2O_3 decorated SnO_2 sensing structures were synthesized by a facile hydrothermal method and characterized by XRD, FESEM, TEM, EDS, and XPS measurements, respectively. Planar chemical gas sensors with the synthesis samples were fabricated, and their sensing performances to C_2H_2 gas were systematically performed and automatically recorded by a CGS-1 TP intelligent gas sensing analysis system. The optimum operating temperature of the Sm_2O_3 decorated SnO_2 based sensor towards 50 μL/L of C_2H_2 is 260℃, and its corresponding response value is 38.12, which is 6 times larger than the pure one. Its response time is about 8-10 s and 10-13 s for recovery time. Meanwhile good stability and reproducibility of the decorated sensor to C_2H_2 gas are also obtained. Furthermore, the proposed sensor exhibits excellent C_2H_2 selectivity among some potential interface gases, like H_2 and CO gas. All sensing results indicate the sensor fabricated with oxide Sm_2O_3 decorated SnO_2 nanorods might be a promising candidate for C_2H_2 detection in practice.