Navy Submarine Academy, Qingdao 266199, China.
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, North Third Ring Road 15, Beijing 100029, China.
Sensors (Basel). 2018 Aug 17;18(8):2710. doi: 10.3390/s18082710.
Nowadays, despite the easy fabrication and low cost of metal oxide gas sensors, it is still challenging for them to detect gases at low concentrations. In this study, resistance-matched p-type Cu₂O and n-type Ga-doped ZnO, as well as p-type CdO/LaFeO₃ and n-type CdO/Sn-doped ZnO sensors were prepared and integrated into p + n sensor arrays to enhance their gas-sensing performance. The materials were characterized by scanning electron microscopy, transmittance electron microscopy, and X-ray diffractometry, and gas-sensing properties were measured using ethanol and acetone as probes. The results showed that compared with individual gas sensors, the response of the sensor array was greatly enhanced and similar to the gas response product of the p- and n-type gas sensors. Specifically, the highly sensitive CdO/LaFeO₃ and CdO/Sn-ZnO sensor array had a high response of 21 to 1 ppm ethanol and 14 to 1 ppm acetone, with detection limits of <0.1 ppm. The results show the effect of sensor array integration by matching the two sensor resistances, facilitating the detection of gas at a low concentration.
如今，尽管金属氧化物气体传感器易于制造且成本低廉，但要检测低浓度的气体仍然具有挑战性。在这项研究中，制备了电阻匹配的 p 型 Cu₂O 和 n 型 Ga 掺杂 ZnO ，以及 p 型 CdO/LaFeO₃ 和 n 型 CdO/Sn 掺杂 ZnO 传感器，并将它们集成到 p + n 传感器阵列中，以提高其气体传感性能。通过扫描电子显微镜、透射电子显微镜和 X 射线衍射对材料进行了表征，并使用乙醇和丙酮作为探针测量了气体传感性能。结果表明，与单个气体传感器相比，传感器阵列的响应得到了极大的增强，并且与 p 型和 n 型气体传感器的气体响应产物相似。具体而言，高灵敏度的 CdO/LaFeO₃ 和 CdO/Sn-ZnO 传感器阵列对 1 ppm 乙醇和 1 ppm 丙酮的响应高达 21 和 14，检测限<0.1 ppm。结果表明，通过匹配两个传感器电阻来实现传感器阵列的集成，可以有效地提高对低浓度气体的检测效果。
