Functional Nanomaterials Laboratory and Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (CAS), Zhongguancun Beiyitiao 2, Haidianqu, Beijing 100190, China.
Environ Sci Technol. 2011 Jul 15;45(14):6088-94. doi: 10.1021/es201121w. Epub 2011 Jun 24.
In this work, quartz crystal microbalance (QCM) sensors for detection of trace hydrogen cyanide (HCN) gas were developed based on nanostructural (flower-like, boat-like, ellipsoid-like, plate-like) CuO. Responses of all the sensors to HCN were found to be in an opposite direction as compared with other common volatile substances, offering excellent selectivity for HCN detection. The sensitivity of these sensors is dependent on the morphology of CuO nanostructures, among which the plate-like CuO has the highest sensitivity (2.26 Hz/μg). Comparison of the specific surface areas of CuO nanostructures shows that CuO of higher surface area (9.3 m(2)/g) is more sensitive than that of lower surface area (1.5 m(2)/g), indicating that the specific surface area of these CuO nanostructures plays an important role in the sensitivity of related sensors. On the basis of experimental results, a sensing mechanism was proposed in which a surface redox reaction occurs between CuO and Cu(2)O on the CuO nanostructures reversibly upon contact with HCN and air, respectively. The CuO-functionalized QCM sensors are considered to be a promising candidate for trace HCN gas detection in practical applications.
在这项工作中，我们基于纳米结构（花状、船状、椭圆形、板状）氧化铜开发了用于检测痕量氢氰酸（HCN）气体的石英晶体微天平（QCM）传感器。与其他常见挥发性物质相比，所有传感器对 HCN 的响应均呈相反方向，为 HCN 检测提供了出色的选择性。这些传感器的灵敏度取决于 CuO 纳米结构的形态，其中板状 CuO 的灵敏度最高（2.26 Hz/μg）。比较 CuO 纳米结构的比表面积表明，比表面积较高（9.3 m(2)/g）的 CuO 比表面积较低（1.5 m(2)/g）的更灵敏，表明这些 CuO 纳米结构的比表面积在相关传感器的灵敏度中起着重要作用。基于实验结果，提出了一种传感机制，即在与 HCN 和空气接触时，CuO 纳米结构上的 CuO 和 Cu(2)O 之间分别发生表面氧化还原反应，且该反应是可逆的。CuO 功能化的 QCM 传感器被认为是实际应用中痕量 HCN 气体检测的有前途的候选者。
