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Deposition of IRMOF-8 thin films by atomic layer deposition was studied at 260–320 °C. Zinc acetate and 2,6-naphthalenedicarboxylic acid were used as the precursors. The as-deposited amorphous films were crystallized in 70% relative humidity at room temperature resulting in an unknown phase with a large unit cell. An autoclave with dimethylformamide as the solvent was used to recrystallize the films into IRMOF-8 as confirmed by grazing incidence x-ray diffraction. The films were further characterized by high temperature x-ray diffraction (HTXRD), field emission scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), time-of-flight elastic recoil detection analysis (TOF-ERDA), nanoindentation, and energy-dispersive x-ray spectroscopy. HTXRD measurements revealed similar behavior to bulk IRMOF-8. According to TOF-ERDA and FTIR, composition of the films was similar to IRMOF-8. Through-porosity was confirmed by loading the films with palladium using Pd(thd)2 (thd = 2,2,6,6-tetramethyl-3,5-heptanedionato) as the precursor.

Ta 2 O 5 /polyimide nanolaminates are deposited at 170 8C by atomic layer deposition (ALD). The precursors are tantalum ethoxide and water for Ta 2 O 5 , and pyromellitic dianhydride (PMDA) and diaminohexane (DAH) for polyimide. The nanolaminates are characterized by X-ray reflection (XRR), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), capacitance and current-voltage measurements, and nanoindentation. The layered structure is confirmed by the XRR data and FESEM images. By controlling the relative thicknesses of the Ta 2 O 5 and polyimide layers, the dielectric and mechanical properties of the nanolaminates are tailored over wide ranges. Dielectric properties of the nanolaminates are improved compared to bare Ta 2 O 5 and polyimide films. Elasticity of the nanolaminate films increases with the polyimide content.

New chemical vapor reaction (CVR) and atomic layer deposition (ALD)-conversion methods were utilized for preparation of metal organic frameworks (MOFs) coatings of solid phase microextraction (SPME) Arrow for the first time. With simple, easy and convenient one-step reaction or conversion, four MOF coatings were made by suspend ALD iron oxide (FeO) film or aluminum oxide (AlO) film above terephthalic acid (HBDC) or trimesic acid (HBTC) vapor. UIO-66 coating was made by zirconium (Zr)-BDC film in acetic acid vapor. As the first documented instance of all-gas phase synthesis of SPME Arrow coatings, preparation parameters including CVR/conversion time and temperature, acetic acid volume, and metal oxide film/metal-ligand films thickness were investigated. The optimal coatings exhibited crystalline structures, excellent uniformity, satisfactory thickness (2-7.5 μm), and high robustness (>80 times usage). To study the practical usefulness of the coatings for the extraction, several analytes with different chemical properties were tested. The Fe-BDC coating was found to be the most selective and sensitive for the determination of benzene ring contained compounds due to its highly hydrophobic surface and unsaturated metal site. UIO-66 coating was best for small polar, aromatic, and long chain polar compounds owing to its high porosity. The usefulness of new coatings were evaluated for gas chromatography-mass spectrometer (GC-MS) determination of several analytes, present in wastewater samples at three levels of concentration, and satisfactory results were achieved.

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