Improvement in Crystallinity and Porosity of Poorly Crystalline Metal–Organic Frameworks (MOFs) through Their Induced Growth on a Well-Crystalline MOF Template

Abstract

Porous metal-organic frameworks (MOFs) are interesting materials owing to their interesting structural features and their many useful properties and applications. In particular, the structural features are greatly important to optimize the MOFs' porosities and so properties. Indeed, the MOFs' well-developed micropore and high surface area are the most important structural features, and as such, many practical applications of MOFs originate from these structural features. We herein demonstrate a strategy for improving the crystallinity of MOFs, and so increasing the porosity and surface area of poorly crystalline MOFs by making them in core-shell-type hybrids through the induced growth on the well-crystalline template. Although poorly crystalline versions of MOFs generate naturally in the absence of the well-crystalline template, well-crystalline versions of MOFs produce inductively in the presence of the well-crystalline template. In addition, the crystallinity enhancement of MOFs brings together the improvement in their porosities and surface areas. The surface areas and pore volumes of the well-crystalline versions of MOFs produced through the induced growth on the template are calculated based on this study, indicating that MOF surface areas increase by up to 7 times compared to the poorly crystalline versions.

Ternary MOF-on-MOF heterostructures with controllable architectural and compositional complexity via multiple selective assembly

“…To date, various architectures of MOF-on-MOF hybrids including core-shell 24 , 27 , 36 , 37 , yolk-shell 25 , asymmetric structure 28 , 38 , 39 and film on film 32 , 40 have been developed. However, the present MOF-on-MOF systems are mainly focused on binary compositions.…”

Metal–Organic Framework‐Based Hybrid Frameworks

“…[ 16 ] For example, Ji et al grew MIL‐68‐X (X = NO 2 or NH 2 ) on a well‐crystallized MIL‐68 template, resulting in improvement of surface area by up to 7 times compared with MIL‐68‐NH 2 . [ 17 ] The enhanced porosity and surface area of the resulted core−shell‐type hybrid MOF material could be due to the improved crystallinity of the MIL‐68‐X (X = NO 2 or NH 2 ) directed by the well‐crystallized MOF‐68 template. Zhang et al synthesized covalent‐bonds‐connected NH 2 ‐UiO‐66/TpPa‐1‐COF hybrid materials, which exhibited an excellent photocatalytic H 2 evolution rate much higher (≈20 times) than the single TpPa‐1‐COF.…”

Polypropylene/Polyvinyl Alcohol/Metal-Organic Framework-Based Melt-Blown Electrospun Composite Membranes for Highly Efficient Filtration of PM2.5

“…Metal-organic frameworks (MOFs) are an emerging class of porous crystalline materials with high porosity [ 20 ] and large surface area [ 21 ]. MOFs have been increasingly used in gas storage and separation fields [ 22 ].…”