Hydrogen sensing ability of Pd-based amorphous alloys

• Published in: Sensors and actuators. B, Chemical Vol. 150; no. 1; pp. 279 - 284
• Main Authors: Kajita, Susumu, Yamaura, Shin-ichi, Kimura, Hisamichi, Inoue, Akihisa
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 21.09.2010
• Subjects: Alloys; Amorphous alloy; Amorphous alloys; Hydrogen absorption; Hydrogen sensor; Impurities; Metallic glasses; Palladium base alloys; Palladium based alloy; Response time; Sensors; Thin films; Hydrogen sensor; Amorphous alloy; Hydrogen absorption; Palladium based alloy
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2010.07.003

Pd-based amorphous alloys have been investigated as materials for hydrogen sensor. We prepared thin films of Pd–Cu–Si alloys that are typical Pd-based amorphous alloys by RF magnetron sputtering method. And we examined their H 2 response by measuring the change of electric resistance of thin films exposed in N 2 and H 2 under various conditions. The thin films of Pd–Cu–Si amorphous alloys showed H 2 responses in wide H 2 concentration range from 1% to 100%. They showed negative correlation between the H 2 response and temperature. The 90% response time was under 1 s at 323 K and 373 K, and it is fast enough for the hydrogen sensor of fuel cell vehicles. We also examined the effect of O 2, H 2O and some impurity gases (CO, CH 4 and CO 2) on the H 2 response. We found that O 2 and H 2O do not affect the H 2 response of the alloys, but the impurity gases delayed the H 2 response time of the alloys at 323 K. However, this effect was reduced by raising the experiment temperature from 323 K to 373 K. These results indicate that the Pd–Cu–Si amorphous alloys have excellent H 2 sensing ability.