Direct Elucidation of the Gas Adsorption Behaviour of Metal-Organic Frameworks (MOFs) by In-situ Single Crystal X-ray Diffraction

金属有机框架（MOFs）形成了最大的一组结晶纳米多孔材料，一直受到全球研究的关注，这一点可以从CA中报道的数千种MOFs中得到证明。在过去20年中发表了21000篇研究论文。M0 F对于包括气体储存和分离技术在内的各种应用具有巨大的潜力，并且作为用于高毒性气体（例如PH 3）的气体储存/释放应用的商业产品以及在防止水果成熟的受控释放产品中销售。M0 F表现出一系列令人兴奋的气体吸附现象，包括滞后，以及当气体如氮气、二氧化碳甲烷、硫化氢被吸附。这些现象往往是由框架结构变化促成的。气体吸附和其他数据已经证明了这些气体吸附现象的存在，并且计算建模提供了对其作用的结构机制的一些预测性见解。然而，在这方面，在这些吸附行为期间，这些材料存在很少的实验确定的晶体结构，这妨碍了对这些新行为的关键理解。本项目旨在通过实验确定某些刚性和柔性框架MOFs在单晶到-在不同的温度和压力下，通过不同的工业相关气体的不同负载量来引发单晶转变。该项目将涉及在单个晶体形式，表征包括单晶和粉末X射线衍射，扫描电子显微镜，气体吸附测量和其他相关的光谱技术。该项目的重点将是使用最先进的单晶X射线衍射仪和毛细管气室使用原位单晶X射线晶体学来获得气体加载的MOFs的晶体结构（工作温度范围100 - 500 K，压力范围0 - 15巴）该项目的成功将使实验确定这些吸附过程的实际机制成为可能，这将对学术界和工业界具有很大的吸引力，通过更深入的了解，将能够增强未来多功能纳米多孔材料的设计。

Metal-organic frameworks (MOFs) form the largest group of crystalline nanoporous material that has been receiving global research attention, as evidenced by the several thousand MOFs reported within the ca. 21000 research papers produced over the past 20 years. MOFs have huge potential for a wide variety of applications including gas storage and separation technologies and are being sold as commercial products for gas storage/ release applications of highly toxic gases, for example, PH3, and in a controlled release product that prevents fruit ripening.MOFs exhibit a range of exciting gas adsorption phenomena including hysteresis, and stepped and gated adsorption when gases such as nitrogen, carbon dioxide, methane, hydrogen disulphide are adsorbed. These phenomena are often facilitated by framework structural changes. Gas adsorption and other data have demonstrated the existence of these gas adsorption phenomena and computational modelling has provided some predicative insight into the structural mechanism of their action. However, few experimentally determined crystal structures exist for these materials during these adsorption behaviours which prevent critical comprehension of these novel behaviours.This project aims to determine the gas adsorption behaviour of certain rigid and flexible framework MOFs by experimentally determining the crystal structures of the MOFs during single crystal-to-single crystal transitions instigated by different loadings of a diverse variety of industrially relevant gases at various temperatures and pressures.The project will involve the synthesis of known or modified MOFs in single crystal form, characterisation including single crystal and powder X-ray diffraction, scanning electron microscopy, gas adsorption measurements and other associated spectroscopic techniques. Particular emphasis of the project will be on using in-situ single crystal X-ray crystallography to obtain the crystal structures of gas loaded MOFs using state-of-the art single crystal X-ray diffractometers and a capillary gas cell (operating temperature range 100 - 500 K, pressure range 0 - 15 bar).Success of the project will enable experimental determination of the actual mechanisms for these adsorption processes that will be highly attractive to the academic and industrial communities and, through greater understanding, will enable enhanced design of future multifunctional nanoporous materials.