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A three-dimensional hierarchical CdO nanostructure with a novel bio-inspired morphology is reported. The field emission scanning electronic microscopy, transmission electron microscopy and X-ray diffractometer were employed to characterize the as-prepared samples. In gas-sensing measurements, acetone and diethyl ether were employed as target gases to investigate cataluminescence (CTL) sensing properties of the CdO nanostructure. The results show that the as-fabricated CdO nanostructure exhibited outstanding CTL properties such as stable intensity, high signal/noise values, short response and recovery time. The limit of detection of acetone and diethyl ether was ca. 6.5 ppm and 6.7 ppm, respectively, which was below the standard permitted concentrations. Additionally, a principal components analysis method was used to investigate the recognizable ability of the CTL sensor, and it was found that acetone and diethyl ether can be distinguished clearly. The performance of the bio-inspired CdO nanostructure-based sensor system suggested the promising application of the CdO nanostructure as a novel highly efficient CTL sensing material., (Copyright © 2014 John Wiley & Sons, Ltd.)

The cataluminescence (CTL) reaction detects the presence and concentration of toxic volatile organic compounds by detecting the luminescence intensity of the different components of the gas mixture. In our study, a cataluminescence online sensor system based on LaCO 3 OH microspheres was developed for the low concentration detection of volatile organic compounds. Multi-dimensional CTL test was carried out to analyse the correlation characteristics of heterogeneous analytes among the catalytic activity, selectivity, sensitivity, response/recover time, stability, and photoelectric signals by changing the parameters of wavelength, flow rate, temperature, and response time under the optimal conditions (280 mL/min, 180ºC, and 480 nm). Due to noise interference received by the CTL signal, the weak CTL signal was filtered based on the time-frequency characteristics of the CTL pattern signal power frequency interference and background noise. Next, this study also studied the mechanism action of the cataluminescence sensor based on LaCO 3 OH microspheres for gas detection, including ethyl ether, acetone, chloroform, and formaldehyde. The principal component analysis (PCA) algorithm was adopted to analyse the CTL patterns, after threshold filtering, the total variance was improved from 89.23% to 98.78% and each vapour gave its unique CTL patterns. Moreover, clustering and identification are discussed to analyse the results, including Hierarchical Cluster Analysis (HCA) and Radial Basis Function Neural Networks (RBFNN), was also discussed. The excellent cluster and recognition ability indicate the feasibility of this CTL sensor for volatile compound determination. • A LaCO 3 OH-microspheres-based cataluminescence sensor was developed for the detection of VOCs firstly. • Multi-dimensional analytes test was carried out among the catalytic activity, selectivity, sensitivity, response/recover time, stability, and photoelectric signals. • Studied the mechanism action of the cataluminescence sensor based on LaCO 3 OH microspheres for gas detection. • The total variance of PCA increased from 89.23% to 98.78% after filtering out the background noise of CTL signal. [ABSTRACT FROM AUTHOR]

Portable sensor system was constructed for detection of acetone vapor based on the cataluminescence (CTL) theory. Excellent microspheres were prepared successfully which increased the contact probability with vapors. The instrument architecture, optimal experiment conditions and measurement characteristics were discussed in detail. The results showed the CTL sensor instrument exhibited excellent CTL properties including visible intensity, high signal/noise (S/N) values, short response time (within 2 s) and recovery time (within 3 s). The sensor instrument covered a linear test range from 5 ppm to 2500 ppm, while the sensor showed non-linearity when concentration ranged from 2500 ppm to 8000 ppm. Furthermore, the sensor system showed outstanding selectivity to acetone compared with other ten kinds of common vapors. Moreover, the CTL sensor also showed an excellent response for H 2 S, the CTL performance of H 2 S under different wavelength and temperature was also discussed. The excellent sensing and online detecting properties proved this sensor instrument to be an excellent candidate for real-time gas contaminant detection. Finally, the sensing control processes and monitoring software interface was also presented. [ABSTRACT FROM AUTHOR]

A three-dimensional hierarchical CdO nanostructure with a novel bio-inspired morphology is reported. The field emission scanning electronic microscopy, transmission electron microscopy and X-ray diffractometer were employed to characterize the as-prepared samples. In gas-sensing measurements, acetone and diethyl ether were employed as target gases to investigate cataluminescence (CTL) sensing properties of the CdO nanostructure. The results show that the as-fabricated CdO nanostructure exhibited outstanding CTL properties such as stable intensity, high signal/noise values, short response and recovery time. The limit of detection of acetone and diethyl ether was ca. 6.5 ppm and 6.7 ppm, respectively, which was below the standard permitted concentrations. Additionally, a principal components analysis method was used to investigate the recognizable ability of the CTL sensor, and it was found that acetone and diethyl ether can be distinguished clearly. The performance of the bio-inspired CdO nanostructure-based sensor system suggested the promising application of the CdO nanostructure as a novel highly efficient CTL sensing material. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]