Borate ester endcapped fluorescent hyperbranched conjugated polymer for trace peroxide explosive vapor detectionElectronic supplementary information (ESI) available: Fourier transform infrared spectra of S3, S2, S1 and the contrast, the GPC and CV curves of S1-S3 polymer, the quenching efficiency (1 − I/I0) of the S1 film on ZnO nanorod array for different vapor pressures of H2O2 after an exposure time of 300 s. See DOI: 10.1039/c5ra02472b

• Main Authors: Chen, Lei, Gao, Yixun, Fu, Yanyan, Zhu, Defeng, He, Qingguo, Cao, Huimin, Cheng, Jiangong
• Format: Journal Article
• Language: English
• Published: 26.03.2015
• ISSN: 2046-2069
• DOI: 10.1039/c5ra02472b

The vapor of peroxide explosives (PEs) is difficult to detect using fluorescent probes because PEs are not typical quenching agents, not having nitro groups or aromatic units that can easily interact with electron-rich probes. Three borate ester endcapped pyrenyl-fluorene copolymers were reported for the detection of PEs, including a hyperbranched polymer ( S1 ) and two linear polymers with borate esters on fluorenyl ( S2 ) or pyrenyl ( S3 ) units. It was found that the hyperbranched polymer S1 has greater steric hindrance, more external borate ester groups, higher HOMO level and higher fluorescence quantum yield, which give it higher sensitivity to H 2 O 2 vapor than S2 and S3 . To further amplify the sensing performance toward H 2 O 2 vapor, a polymer/ZnO nanorod array composite was used, exploiting the catalytic ability and high area to volume ratio of the ZnO nanorod array. The fluorescence of the S1 film is quenched by ∼60% and ∼30% under saturated vapor of H 2 O 2 and TATP, respectively, for 300 s at room temperature, and the detection limit for H 2 O 2 is estimated to be 1.6 ppb. These results reveal that the S1 /ZnO nanorod array composite is very promising for the preparation of a highly sensitive fluorescence device for detecting the vapor of peroxide explosives. The hyperbranched polymer S1 /ZnO nanorod array composite is very promising for a highly sensitive fluorescence device for detecting peroxide explosives.