Influences of Impurity Gases in Air on Room-Temperature Hydrogen-Sensitive Pt–SnO<sub>2</sub> Composite Nanoceramics: A Case Study of H<sub>2</sub>S
Xilai Lu,
Menghan Wu,
Yong Huang,
Jiannan Song,
Yong Liu,
Zhiqiao Yan,
Feng Chen,
Jieting Zhao,
Wanping Chen
Affiliations
Xilai Lu
Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
Menghan Wu
Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
Yong Huang
Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
Jiannan Song
Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
Yong Liu
Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
Zhiqiao Yan
Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510650, China
Feng Chen
Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application, Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510650, China
Jieting Zhao
Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
Wanping Chen
Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072, China
The slight but cumulative influence of impurity gases in air poses a great threat to the long-term stability of room-temperature gas sensors. Room-temperature hydrogen-sensitive Pt–SnO2 composite nanoceramics of 5 wt% Pt were prepared through pressing and sintering. The response of a sample was over 10,000 after being exposed to 500 ppm H2S–20% O2–N2 at room temperature, and the room-temperature hydrogen sensing capacity was seriously degraded even for samples that had aged dozens of days since H2S exposure. Mild heat treatments such as 160 °C for 10 min were found able to fully activate those H2S-exposed samples. As the peak of S 2p electron was clearly detected in H2S-exposed samples, it was proposed that for room-temperature hydrogen-sensitive Pt–SnO2 composite nanoceramics, H2S exposure induced degradation results from the poisoning of Pt by H2S deposited on it, which can be removed through a mild heat treatment. Periodic mild heat treatment should be a convenient and effective measure for room-temperature metal oxide gas sensors to achieve long-term stability through preventing the accumulation of impurity gases in air deposited on them.
