Highly sensitive breath sensor based on sonochemically synthesized cobalt-doped zinc oxide spherical beads

Ultrasonics Sonochemistry

Tae Il Lee¹  Chang Hee Cho²  Soosang Chae³  Yong-Sahm Choe⁴ 

[1] Corresponding authors.;Department of Materials Science and Engineering, Gachon University, Seong-nam, Gyeonggi 13120, Korea;IPF - Leibniz-Institut für Polymerforschung Dresden e.V, Institute of Physical Chemistry and Polymer Physics, 01069 Dresden, Germany;iSenLab Inc. Dunchondae-ro 545, Jungwong-gu, Seong-nam, Gyeonggi, Korea;

关键词: Sonochemical synthesis;    Metal oxide;    Co-doped ZnO;    Acetone sensor;    Exhalation diagnostic;   

DOI  :  

来源: DOAJ

【 摘 要 】

In this study, we introduce cobalt (Co)-doped zinc oxide (ZnO) spherical beads (SBs), synthesized using a sonochemical process, and their utilization for an acetone sensor that can be applied to an exhalation diagnostic device. The sonochemically synthezied Co-doped ZnO SBs were polycrystalline phases with sizes of several hundred nanometers formed by the aggregation of ZnO nanocrystals. As the Co doping concentration increased, the amount of substitutionally doped Co2+ in the ZnO nanocrystals increased, and we observed that the fraction of Co3+ in the Co-doped ZnO SBs increased while the fraction of oxygen vacancies decreased. At an optimal Co-doping concentration of 2 wt%, the sensor operating temperature decreased from 300 to 250 °C, response to 1 ppm acetone improved from 3.3 to 7.9, and minimum acetone detection concentration was measured at 43 ppb (response, 1.75). These enhancements are attributed to the catalytic role of Co3+ in acetone oxidation. Finally, a sensor fabricated using 2 wt% Co-doped ZnO SBs was installed in a commercially available exhalation diagnostic device to successfully measure the concentration of acetone in 1 ml of exhaled air from a healthy adult, returning a value of 0.44 ppm.

【 授权许可】

Unknown