Porous coordination polymers (PCPs) or metal-organic frameworks (MOFs) have been extensively studied for their diversified and designable/tailorable framework and pore structures. Compared with conventional porous materials, MOFs have much larger framework flexibility, which can give rise to not only various types of interesting structural responses and dynamic behaviors toward external stimuli, but also significantly improved performances for storage, separation, sensing and other applications.
Therefore, controlling the flexibility of MOFs, or rational design and synthesis of MOFs with specified flexibility and dynamism, are of practical importance. However, framework flexibility is simultaneously controlled by many factors, and trivial difference of a structural parameter or other factor related with the sample or environment can drastically change the response. In other words, framework flexibility can be more difficult to design or control, compared with the static features such as framework and pore structures.
In a new review published in the Beijing-based journal National Science Review, scientists at the Sun Yat-Sen University in Guangzhou, China present the advances in designing/controlling the flexibility of MOFs. Co-authors Jie-Peng Zhang, Hao-Long Zhou, Dong-Dong Zhou, Pei-Qin Liao and Xiao-Ming Chen first define and distinguish the concepts of controlling the structure of flexible MOFs and controlling the flexibility of MOFs.
The former refers to the change of framework structures of flexible MOFs toward external chemical (guest adsorption/desorption/exchange) and physical (temperature, light, pressure, etc.) stimuli, which is the intrinsic property of flexible MOFs and has been the topics of most researches. On the other hand, the latter uses external environment to modulate the structural response and dynamic behavior of MOFs, or designs/synthesizes new MOF materials/samples to generate specified structural response and dynamic behavior toward a given external stimulus.
Based on discussions of representative examples, they systematically summarize the basic strategies for designing/controlling flexibility of MOFs, i.e., design, synthesis, and modification of the porous host, controlling the composition and size/morphology of the porous crystal sample, and controlling the external physical environment, in which the target gradually changes from designing new materials to modulating the property of existing materials.
The scientists emphasize that, "It should be pointed out that, designing, tailoring, or controlling framework flexibility is not only useful for understanding the structure-property relationship of MOFs, but also a new dimension for developing MOF materials with excellent performances for molecular recognition, high storage/delivery capacity, selective separation, abnormal/controllable thermal expansion, and so on."
This work was supported by the National Basic Research Program of China (973 Project, 2014CB845602) and the National Natural Science Foundation of China (21290173 and 21473260)
See the article:
Jie-Peng Zhang, Hao-Long Zhou, Dong-Dong Zhou, Pei-Qin Liao, and Xiao-Ming Chen
Controlling flexibility of metal-organic frameworks
Natl Sci Rev, 2017, doi: 10.1093/nsr/nwx127
The National Science Review is the first comprehensive scholarly journal released in English in China that is aimed at linking the country's rapidly advancing community of scientists with the global frontiers of science and technology. The journal also aims to shine a worldwide spotlight on scientific research advances across China.
Jie-Peng Zhang | EurekAlert!
Graphene origami as a mechanically tunable plasmonic structure for infrared detection
25.04.2018 | University of Illinois College of Engineering
Scientists create innovative new 'green' concrete using graphene
24.04.2018 | University of Exeter
Magnetic resonance imaging, or MRI, is a widely used medical tool for taking pictures of the insides of our body. One way to make MRI scans easier to read is...
At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.
Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
26.04.2018 | Power and Electrical Engineering
26.04.2018 | Life Sciences
26.04.2018 | Power and Electrical Engineering