title: CuO nanostructures as quartz crystal microbalance sensing layers for detection of trace hydrogen cyanide gas.
abstract: 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.
authors.affiliation: 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.
authors.forename: Mingqing
authors.initials: M
authors.lastname: Yang
authors.forename: Junhui
authors.initials: J
authors.lastname: He
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Hu
authors.forename: Chunxiao
authors.initials: C
authors.lastname: Yan
authors.forename: Zhenxing
authors.initials: Z
authors.lastname: Cheng
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D003300:Copper / Q000737:chemistry*; D004784:Environmental Monitoring / Q000295:instrumentation* / Q000379:methods; D006856:Hydrogen Cyanide / Q000032:analysis*; D013058:Mass Spectrometry; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures / Q000737:chemistry*; D058525:Quartz Crystal Microbalance Techniques / Q000295:instrumentation* / Q000379:methods; D014961:X-Ray Diffraction
chemical_list: D000393:Air Pollutants; D006856:Hydrogen Cyanide; D003300:Copper; C030973:cupric oxide