Chemistry Seminar - Why squeeze MOFs? The Effect of Pressure, Guest Uptake and Structural Flexibility on Porous Materials

Title: Why squeeze MOFs? The Effect of Pressure, Guest Uptake and Structural Flexibility on Porous Materials

Speaker:  Prof Stephen Moggach, University of Western Australia

Abstract: Over the last 10 years or so, several researchers have been studying the effect of high pressure (generally considered as > 0.1 GPa) on porous and non-porous molecular and non-molecular systems, such as metal-organic frameworks (or MOFs).  But why?  Application of pressure has proven to be an incredibly valuable route to developing structure/property relationships in a whole host of functional materials, including single-molecule magnets and molecular conductors.  In the world of porous materials, we have been using high-pressure crystallographic techniques to explore the uptake of guest species into the cavities and channels inside MOFs and other porous molecular materials.  We do this, by taking advantage of the fact that the small molecules that encompass the pressure transmitting fluids used frequently in high-pressure crystallographic studies can penetrate the pores on increasing pressure.  This has revealed unexpected flexibility, explain unusual adsorption phenomena under milder gas pressures, overcome crystallite size-dependent phenomena, and increase reactivity in MOFs, letting us develop structure-property relationships in this group of fascinating materials.  Here, we will give an overview of the effect of high-pressure on both micro and nanoporous materials and highlight some of our recent work on gas-loaded and non-stoichiometric framework materials, and show you why, you should really squeeze your MOFs.

Bio: Stephen received his BSc degree in applied chemistry from The Robert Gordon University (2002) and his PhD in chemistry from the University of Edinburgh (2006). Stephen did his PhD then a postdoc under the supervision of Professor Simon Parsons at the University of Edinburgh in the field of high-pressure crystallography. Stephen went on to become a lecturer then senior lecturer in inorganic chemistry and Royal Society of Edinburgh Personal Research Fellow in Edinburgh before heading to the University of Western Australia in 2018. In 2020 he was awarded a Future Fellowship and in 2024 became a Professor in Chemistry. He is active in the crystallographic community and is a member of the IUCr commission for high-pressure, is a co-editor for Acta C. and J. Appl. Cryst., and was a lecturer at the Durham Crystallography school in the UK and now teaches and helps coordinate the SCANZ crystallography school here in Australia.