Selective coordination with heterogeneous metal atoms for inorganic–organic hybrid layers

The fabrication of a metal–organic nanostructure was demonstrated by the hybrid synthesis process. The metal atoms such as Sn and Zn were sequentially coordinated on specific functional groups of the main organic layer by vapor phase metalation.

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Vapor-phase linker exchange of metal-organic frameworks

Science Advances ◽

10.1126/sciadv.aax7270 ◽

2020 ◽

Vol 6 (18) ◽

pp. eaax7270 ◽

Cited By ~ 7

Author(s):

Wufeng Wu ◽

Jingyi Su ◽

Miaomiao Jia ◽

Zhanjun Li ◽

Guoqiang Liu ◽

...

Keyword(s):

Functional Groups ◽

Vapor Phase ◽

Metal Organic Frameworks ◽

Building Blocks ◽

Improve Performance ◽

Environment Friendly ◽

Postsynthetic Modification ◽

Metal Organic ◽

Molecular Affinity ◽

Linker Exchange

Metal-organic frameworks (MOFs) have been attracting intensive attention because of their commendable potential in many applications. Postsynthetic modification for redesigning chemical characteristics and pore structures can greatly improve performance and expand functionality of MOF materials. Here, we develop a versatile vapor-phase linker exchange (VPLE) methodology for MOF modification. Through solvent-free and environment-friendly VPLE processing, various linker analogs with functional groups but not for straightforward MOF crystallization are inserted into frameworks as daughter building blocks. Besides single exchange for preparing MOFs with dual linkers, VPLE can further be performed by multistage operations to obtain MOF materials with multiple linkers and functional groups. The halogen-incorporated ZIFs exhibit good porosity, tunable molecular affinity, and impressive CO2/N2 and CH4/N2 adsorption selectivities up to 31.1 and 10.8, respectively, which are two to six times higher than those of conventional adsorbents. Moreover, VPLE can substantially enhance the compatibility of MOFs and polymers.

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Study on Porosity in Zinc Oxide Ultrathin Films from Three-Step MLD Zn-Hybrid Polymers

Materials ◽

10.3390/ma14061418 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1418

Author(s):

Richard Berger ◽

Martin Seiler ◽

Alberto Perrotta ◽

Anna Maria Coclite

Keyword(s):

Molecular Layer ◽

Ambient Air ◽

Zno Films ◽

Organic Layers ◽

Organic Hybrid ◽

Hybrid Thin Films ◽

Metal Organic ◽

Mesoporous Zno ◽

Hybrid Layers ◽

First Time

Deriving mesoporous ZnO from calcinated, molecular layer deposited (MLD) metal-organic hybrid thin films offers various advantages, e.g., tunable crystallinity and porosity, as well as great film conformality and thickness control. However, such methods have barely been investigated. In this contribution, zinc-organic hybrid layers were for the first time formed via a three-step MLD sequence, using diethylzinc, ethanolamine, and maleic anhydride. These zinc-organic hybrid films were then calcinated with the aim of enhancing the porosity of the obtained ZnO films. The saturation curves for the three-step MLD process were measured, showing a growth rate of 4.4 ± 0.2 Å/cycle. After initial degradation, the zinc-organic layers were found to be stable in ambient air. The transformation behavior of the zinc-organic layers, i.e., the evolution of the film thickness and refractive index as well as the pore formation upon heating to 400, 500, and 600 °C were investigated with the help of spectroscopic ellipsometry and ellipsometric porosimetry. The calculated pore size distribution showed open porosity values of 25%, for the sample calcinated at 400 °C. The corresponding expectation value for the pore radius obtained from this distribution was 2.8 nm.

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Solvent-Free Powder Synthesis and MOF-CVD Thin Films of the Mesoporous Metal-Organic Framework MAF-6

10.26434/chemrxiv.9860891.v1 ◽

2019 ◽

Author(s):

Timothée Stassin ◽

Ivo Stassen ◽

Joao Marreiros ◽

Alexander John Cruz ◽

Rhea Verbeke ◽

...

Keyword(s):

Vapor Phase ◽

Metal Organic Framework ◽

Chemical Vapor ◽

Uptake Capacity ◽

Powder Synthesis ◽

Crystalline Films ◽

Metal Organic ◽

Mesoporous Metal ◽

First Time ◽

Organic Framework

A simple solvent- and catalyst-free method is presented for the synthesis of the mesoporous metal-organic framework (MOF) MAF-6 (RHO-Zn(eIm)2) based on the reaction of ZnO with 2-ethylimidazole vapor at temperatures ≤ 100 °C. By translating this method to a chemical vapor deposition (CVD) protocol, mesoporous crystalline films could be deposited for the first time entirely from the vapor phase. A combination of PALS and Kr physisorption measurements confirmed the porosity of these MOF-CVD films and the size of the MAF-6 supercages (diam. ~2 nm), in close agreement with powder data and calculations. MAF-6 powders and films were further characterized by XRD, TGA, SEM, FTIR, PDF and EXAFS. The exceptional uptake capacity of the mesoporous MAF-6 in comparison to the microporous ZIF-8 is demonstrated by vapor-phase loading of a molecule larger than the ZIF-8 windows.

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