Pd/In2O3-based bilayer H2 sensor with high resistance to silicone toxicity and ultra-fast response
Hydrogen sensors are easily deactivated by hexamethyldisiloxane (HMDSO) poisoning. Moreover, the existing anti-poisoning strategies can also damage the overall sensing performance of these hydrogen sensors. Therefore, a new bilayer design with a Pd/In 2 O 3 sensitive layer and an In 2 O 3 /Al 2 O 3 catalytic filter layer is proposed to avoid the deactivation of hydrogen sensors. The In 2 O 3 /Al 2 O 3 layer helps in hindering HMDSO and its decomposition products from reaching the Pd/In 2 O 3 layer. The H 2 response of the sensors is enhanced due to the small size of In 2 O 3 and the electronic sensitization of Pd. As a result, the bilayer sensors exhibit high response (Ra/Rg = 53) and ultra-fast response time (1 s) towards 3000 ppm H 2 at 365 °C. The resistance and the H 2 response of the bilayer sensors are almost unchanged after 40 min of 10 ppm HDMSO poisoning. In this paper, the mechanism of resistance against silicone poisoning and the H 2 response of the bilayer sensors are discussed from the separation of sensing and catalytic filtration reactions to the behavior of adsorbed oxygen.
危险品化学品经营许可证(带存储)