Wang Wei, Zhang Qinyi, Lv Ruonan, Wu Dong, Zhang Shunping
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
Sensors (Basel). 2021 Jun 8;21(12):3947. doi: 10.3390/s21123947.
High performance formaldehyde gas sensors are widely needed for indoor air quality monitoring. A modified layer of zeolite on the surface of metal oxide semiconductors results in selectivity improvement to formaldehyde as gas sensors. However, there is insufficient knowledge on how the thickness of the zeolite layer affects the gas sensing properties. In this paper, ZSM-5 zeolite films were coated on the surface of the SnO gas sensors by the screen printing method. The thickness of ZSM-5 zeolite films was controlled by adjusting the numbers of screen printing layers. The influence of ZSM-5 film thickness on the performance of ZSM-5/SnO gas sensors was studied. The results showed that the ZSM-5/SnO gas sensors with a thickness of 19.5 μm greatly improved the selectivity to formaldehyde, and reduced the response to ethanol, acetone and benzene at 350 °C. The mechanism of the selectivity improvement to formaldehyde of the sensors was discussed.
室内空气质量监测广泛需要高性能甲醛气体传感器。在金属氧化物半导体表面修饰一层沸石可提高气体传感器对甲醛的选择性。然而，关于沸石层厚度如何影响气敏性能的了解还不够充分。本文采用丝网印刷法在SnO气体传感器表面涂覆ZSM-5沸石薄膜。通过调整丝网印刷层数来控制ZSM-5沸石薄膜的厚度。研究了ZSM-5薄膜厚度对ZSM-5/SnO气体传感器性能的影响。结果表明，厚度为19.5μm的ZSM-5/SnO气体传感器在350℃时对甲醛的选择性有很大提高，对乙醇、丙酮和苯的响应降低。探讨了传感器对甲醛选择性提高的机理。
