Hierarchical CdO/ZnO composite materials composed of porous nanoplates are prepared by simple thermal treatment of a "pre-synthesized" cadmium-zinc bimetallic carbonate precursor. The gas-sensing properties of the as-synthesized nanocomposites are evaluated by a range of gases and organic vapors, and the results show that the gas sensors based on CdO/ZnO nanocomposites exhibit the highest sensing response towards ethanol relative to other testing gases. The optimal ratio of CdO to ZnO in CdO/ZnO nanocomposites is 7.5:100 for ethanol detection. The highest response of CdO/ZnO is ∼7 and 59 times as high as those of the pure ZnO and the pure CdO, respectively. The significantly enhanced sensing performance of the CdO/ZnO nanocomposite is attributed to its novel hierarchical structure and synergetic effect between CdO and ZnO. In addition, the CdO/ZnO sensor exhibits short response and recovery times (<10 s) and a wide response range from 0.5 to 500 ppm for ethanol detection. In the testing range from 0.5 to 500 ppm, the logarithm of sensitivity shows a good linear dependency on the logarithm of ethanol concentration, indicating that the CdO/ZnO sensor may be used for quantitative detection of ethanol vapor. © 2014 Elsevier B.V. All rights reserved.
Zhou, L. J., Li, C., Zou, X., Zhao, J., Jin, P. P., Feng, L. L., … Li, G. D. (2014). Porous nanoplate-assembled CdO/ZnO composite microstructures: A highly sensitive material for ethanol detection. Sensors and Actuators, B: Chemical, 197, 370–375. https://doi.org/10.1016/j.snb.2014.02.086