Growth of metal–organic framework HKUST-1 in capillary using liquid-phase epitaxy for open-tubular capillary electrochromatography and capillary liquid chromatography

• Published in: Journal of Chromatography A 2015-02, Vol.1381, p.239-246
• Main Authors: Bao, Tao, Zhang, Juan, Zhang, Wenpeng, Chen, Zilin
• Format: Article
• Language: English
• Subjects: Benzene; Capillarity; Capillary electrochromatography; Chromatography; Columns (process); Electrochromatography; Epitaxy; HKUST-1; Liquid-phase epitaxy; Metal-organic frameworks; Metalorganic compounds; Metal–organic framework; Phases
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2015.01.005

•A novel method is developed for the coating of capillary with HKUST-1.•HKUST-1 layer is grown in capillary using liquid-phase epitaxy for the first time.•The HKUST-1@capillary can be applied to both OT-CEC and OT-CLC modes.•The prepared columns exhibit good stability, repeatability and high efficiency. Much attention is being paid to applying metal–organic frameworks (MOFs) as stationary phases in chromatography because of their fascinating properties, such as large surface-to-volume ratios, high levels of porosity, and selective adsorption. HKUST-1 is one of the best-studied face-centered-cubic MOF containing nano-sized channels and side pockets for film growth. However, growth of HKUST-1 framework inside capillary column as stationary phase for capillary electrochromatography is a challenge work. In this work, we carry out the growth of HKUST-1 on the inner wall of capillary by using liquid-phase epitaxy process at room temperature. The fabricated HKUST-1@capillary can be successfully used for the separation of substituted benzene including methylbenzene, ethylbenzene, styrene, chlorobenzene, bromobenzene, o-dichlorobenzene, benzene series, phenolic acids, and benzoic acids derivates. High column efficiency of 1.5×105N/m for methylbenzene was achieved. The formation of HKUST-1 grown in the capillary was confirmed and characterized by scanning electron microscopy images, Fourier transform infrared spectra and X-ray diffraction. The column showed long lifetime and excellent stability. The relative standard deviations for intra-day and inter-day repeatability of the HKUST-1@capillary were lower than 7%.