Electrosynthesis of metal coordination cluster Zn5/polyaniline composite coating for headspace solid phase microextraction of nine volatile phenolic compounds in aqueous samples

A novel polyaniline (PANI) coating doped with Zn5(H2Ln)6(NO3)4 (Zn5, H3Ln=(1,2-bis(benzimidazole-2-yl)ethenol) cluster on a stainless-steel wire was prepared by the electrodeposition method for the headspace solidphase microextraction (HS-SPME) of nine volatile phenols. Scanning electron microscopy, Fourier transform infrared spectrometry, energy dispersive spectrometry and thermogravimetry were employed to characterize the morphology, composition, structure and thermal stability of the Zn5/PANI composite coating. The extraction efficiency of the Zn5/PANI composite coating for nine phenols was nearly 2 times higher than that of pure PANI coating. After the extraction conditions were optimized, an HS-SPME-gas chromatography-flame ionization detector (GC-FID) method was developed for the determination of nine phenols in water samples. The HS-SPMEGC-FID method had superior analytical performance with good linearities (0.05-50.0 mu g/L) and low limits of detection (0.01-0.08 mu g/L). Then, the proposed method was successfully applied for the determination of nine phenols in water samples with satisfactory recoveries (79.4-110.0%).