Synthesis and sensitive properties of poly-(bistriethylphosphine)-platinum-diethynylbenzene for organic vapor detection

Poly-(bistriethylphosphine)-platinum-diethynylbenzene (Pt-DEB) was synthesized by dehydrohalogenation reaction. X-ray photoelectron spectroscopy (XPS), FTIR, and ¹H-NMR spectra were used to identify the formation of Pt-DEB target material. Sensitive properties of Pt-DEB-based quartz crystal microbalance (QCM) sensor to various organic vapors such as trichloromethane, tetrahydrofuran, acetone, isopropyl alcohol, ethanol, and methanol have been studied. The results show that Pt-DEB has good reversibility, reproducibility, and linear sensitivity to organic vapors at room temperature. The sensitivity of Pt-DEB (dissolved in CHCl₃) toward CHCl₃ is clearly higher than that toward other analytes, and a larger molecular weight of alcohol has a higher sensitivity response. The Pt-DEB-based QCM gas sensor shows low detection limits ranging from 1.0 to 3.56 ppm for the organic vapors and stable performance during a period of 30 days.