Superior enhancement of NO<sub>2sub> gas response using n-p-n transition of carbon nanotubes/SnO<sub>2sub> nanowires heterojunctions
详细信息 查看全文
- 作者：Quan Thi Minh Nguyet<sup>asup><sup> ; sup><sup>bsup>Author Vitae ; Nguyen Van Duy<sup>asup><sup> ; sup><sup>1sup><sup> ; sup><sup>nguyenvanduy@itims.edu.vn" class="auth_mail" title="E-mail the corresponding authorsup>Author Vitae ; Nguyen Thi Phuong<sup>asup>Author Vitae ; Nguyen Ngoc Trung<sup>bsup>Author Vitae ; Chu Manh Hung<sup>asup>Author Vitae ; Nguyen Duc Hoa<sup>asup>Author Vitae ; Nguyen Van Hieu<sup>asup><sup> ; sup><sup>1sup><sup> ; sup><sup>hieu@itims.edu.vn" class="auth_mail" title="E-mail the corresponding authorsup>Author Vitae
- 关键词：CNTs/SnO2 NWs ; n-p-n heterojunction ; Gas sensors ; ppb level NO2
- 刊名：Sensors & Actuators: B. Chemical
- 出版年：2017
- 出版时间：January 2017
- 年：2017
- 卷：238
- 期：Complete
- 页码：1120-1127
- 全文大小：2049 K
文摘
The enhancement of sensor performances for the detection of highly toxic NO<sub>2sub> gas is one of the most important technological issues in the realization of devices for environmental pollution monitoring. Herein, the n-p-n heterojunctions of carbon nanotubes (CNTs) and SnO<sub>2sub> nanowires (NWs) are designed and fabricated by a facile method to investigate their NO<sub>2sub> gas-sensing performance. The designed devices are easily realized by first growing the SnO<sub>2sub> NWs on Pt electrodes using a thermal chemical vapour deposition method and then spray coating the single-walled carbon nanotubes (SWCNTs) and/or multi-walled carbon nanotubes (MWCNTs) to make a connection between the two electrodes. The MWCNTs/SnO<sub>2sub> NWs device has much higher NO<sub>2sub> responsiveness compared to the SWCNTs/SnO<sub>2sub> NWs and the pristine SnO<sub>2sub> NWs devices. The fabricated devices showed ultrahigh enhancement in gas sensing performance for NO<sub>2sub>, whereas these characteristics do not significantly improve for H<sub>2sub>S gas. At a low working temperature of 100 °C, the fabricated sensors are able to detect the NO<sub>2sub> gas concentration down to 20 ppb. We also clarify the sensing mechanism of the fabricated devices.