PhD Title: Structure-property relations of flexible framework solids for carbon dioxide storage

Supervisor: Professor Simon Redfern

Advisors: Dr Stuart Clarke, Dr Richard Harrison, Dr Gareth Lloyd (Materials Chemistry Group, Department of Chemistry)

Description:

The utilisation of carbon dioxide has become a worldwide interest. My PhD thesis mainly focuses on the structural behaviours and physical properties of the guest-host system formed by zeolite-like Metal Organic Frameworks (MOFs) and CO2, aiming to find out the mechanism of MOFs' oustanding gas absorption, seperation and storage properties. Currently my main research is based on Zeolite Imidazolate Frameworks (ZIFs).

MOFs are three-dimensional networks consisting of metal cations/clusters linked through bridging organic ligands, e.g. terephthalic acid, trimesic acid. Among numbers of MOF subfamilies, Zeolite Imidazolate Frameworks (ZIFs) are well-known for their zeolitic structure as the 145 degree angle at the bridging imidazole family ligands is coincident with the Si–O–Si angle in zeolites, as seen in the figure below.

                               

In recent studies, ZIFs’ large gas capacity were claimed due to their framework flexibility, sometimes the so-called ‘gate-opening behaviour’, whereas no sufficient crystallographic proof was given. Meanwhile, such a flexible structure has been discovered may undergo solid phase transitions under extreme external conditions. In ZIF-1, 3, 4, a ‘crytalline-amorphisation-recrystallisation’ phenomenon was found under high temperature as well as high pressure, and was interpreted as a ‘ZIF-a-ZIF-ZIF-zni’ phase transition procedure; in ZIF-8, the pore size was found to increase with pressure and at 1.47 GPa a high-pressure phase was formed. In order to understand the realtionship between ZIFs' CO2 absorption process and their framework flexibility, it is important to conduct a systematic research on the structural behaviours and potential phase transitions of typical ZIFs in CO2 environment, and further the interactions between the crystalline host and the guest molecules.

The main research method involves common material sciences analysis techniques, e.g. X-Ray Diffraction, Raman Spectroscopy, Thermogravimetric Analysis. More specialised techniques using neutron and synchrotron light sources are also be applied.

Links to related research groups:

Professor Tony Cheetham, Functional Inorganics and Hybrid Materials Group, Department of Materials Science & Metallurgy, University of Cambridge

Professor Omar Yaghi, Yaghi Laboratory, Department of Chemistry, UC Berkeley

Brief Curriculum Vitae:

Education

2011-2015 (expected)   Ph.D. in Mineral Physics, University of Cambridge, UK
2007-2011                     B.Sc. in Chemistry, Fudan University, P. R. China

Previous Research Projects

1. SPE-HPLC based vitamin B and D determination in infant milk powder and animal feed, DSM China Nutrition Center, DSM (China) Ltd., Royal DSM N. V., 2010-2011;
2. Conversion of methanol-gasoline/olefins (MTG/MTO) over modified ZSM-5, Institute of Coal Chemistry, Chinese Academy of Sciences, 2009;
3. Synthesis and characterisation of novel Metal-Organic Frameworks (MOFs), Department of Chemistry, Fudan University, 2008-2010.

Research Skills

Softwares: GSAS, Topas 4, DASH 3.3, EXPO, Fox, Mercury, ConQuest, Material Studio, Igor Pro, ChemOffice.


Publications: 2006-Present

Last updated on 23-Jan-13 11:57