Nanostructured molybdenum oxide in a 3D metal organic framework
and in a 2D polyoxometalate network for extraction of chlorinated
benzenes prior to their quantification by GC–MS
Habib Bagheri, Faezeh Karimi Zandian, Hasan Javanmardi, Alireza Abbasi, Tahereh Golzari Aqda
Microchimica Acta 185 (2018) 536
doi: 10.1007/s00604-018-3070-5
A three–dimensional metal organic framework (3D–MOF) and a two–dimensional polyoxometalate (2D–POM), both incorporating nanostructured molybdenum (VI) oxide, were synthesized and implemented for headspace needle trap extraction of traces of chlorobenzenes (CBs). The 3D–MOF of type {(Mo2O6)(4,4′–bpy)}n and the 2D–POM of type [4,4′–bpy][Mo7O22] were
synthesized by a solvothermal process and characterized by FT–IR, powder X–ray diffraction, scanning electron microscopy,
transmission electron microscopy, thermogravimetry, energy dispersive X–ray, elemental mapping and Brunner–Emmet–Teller
adsorption analyses. The 3D–MOF proved to be superior. Following thermal desorption, the CBs (monochlorobenzene, 1,4–
dichlorobenzene, 1,2–dichlorobenzene, 1,2,4–trichlorobenzene and 1,2,3,4-tetrachlorobenzene) were quantified by GC–MS.
Under optimized conditions, the calibration plots are linear in the 1–1000 ng.L-1 concentration range, and the limits of detection
range from 0.2 to 2 ng.L-1. The intra– and inter–day relative standard deviations for three replicates at levels of 10 and 200 ng.L-1 are in the range of 5–12% and 10–15%, respectively. The needle–to–needle reproducibility was also found to be in the range of
6–13%. The application of the method to the analysis of various spiked real water samples resulted in recoveries between 84 and
114%.