Nano-Integration of Metal-Organic Frameworks and Catalysis for the Uptake and Utilisation of CO₂

This project focuses on one-step CO₂ capture and utilisation.

Nano-scale-integration of CO₂ uptake and utilisation processes will provide new highly efficient single-step processes to turn CO₂ into useful products (polymers, carbohydrates and fuels). Metal Organic Frameworks (MOFs) have emerged as a front-runner in the uptake and storage of CO₂. Effective catalysts for the conversion of CO₂ into useful chemical products have already been discovered but industrial CO₂ waste streams with high CO₂ concentrations are used.

In this project these two areas of existing strength are combined to provide new nano-structured functional catalyst membranes tailored to both capture and concentrate CO₂ from the free atmosphere and convert CO₂ into useful products in a single continuous process. The supply and reactivity of CO₂ to the catalyst surface will be enhanced leading to effective reduction of atmospheric CO₂. The developed technology will be entirely new; based on functionalised and specifically tailored MOF-membranes. The catalytic processes will be driven by solar energy (bio-catalysis), renewable energy and waste heat from carbon creating processes.

Current Projects

• Contribution to the Nanotech Grand Challenge Project
• Electrochemical Conversion of CO2 in Porous Media
• Catalyst Design and Synthesis for the Conversion of Carbon Dioxide into Commodity Chemicals
• Synthesis of metal-organic framework materials for CO2 capture

Research highlights

Making MOF Membranes

New methods for the preparation of thin films of the metal-organic framework MIL-101(Cr), Cr3OF(H2O)2(bdc)3 (bdc = 1,4-benzenedicarboxylate), on porous alumina supports have been developed. These rely on the initial formation of nanoparticles of the MOFs [1], which are either formed in situ close to the surface [2] or applied to the support by dip-coating in the presence of a polymer [3].

The MOF films can be made hydrophobic by post-synthetic modification with an aliphatic carboxylic acid. The amino-functionalised analogue of MIL-101(Cr) has also been prepared, and has been modified using a new tandem covalent post-synthetic modification protocol, whereby the MOF is first treated with sodium nitrite in the presence of acid to convert it into a diazonium salt, then this is further reacted to form either a halo- or an azo dye-functionality [4]. The azo dye-modified MOF was found to have considerably enhanced selectivity for CO2 over N2, especially at low partial pressures.

[1] D. Jiang, A. D. Burrows and K. J. Edler, CrystEngComm, 2011, 13, 6916.
[2] D. Jiang, A. D. Burrows, R. Jaber and K. J. Edler, Chem. Commun., 2012, 48, 4965.
[3] D. Jiang, A. D. Burrows, Y. Xiong, and K. J. Edler, manuscript in preparation.
[4] D. Jiang, L. L. Keenan, A. D. Burrows and K. J. Edler, Chem. Commun., 2012, 48, 12053.

Electrochemistry within Metal-Organic Frameworks (MOFs)

A wide range of redox processes within porous MOF materials and study the link between electron exchange and ion exchange. Many benzoate-based materials are hydrolytically unstable with redox reactivity being dominated by irreversible pore degradation [1,2]. However, for adsorbed redox dyes with positive charge reversibility increased [3] and processes inside of MOF pores are observed.

More importantly, a new “conformal transformation” of Co-MOF-71 to cobalt hydroxide has been discovered [4] where the shape of the crystal remains, but the chemical nature of the material is completely different after exposure to aqueous alkaline solution. This methodology will allow novel porous membrane and catalyst support materials to be produced.

[1] Halls, J.E.; Hernan-Gomez, A.; Burrows, A.D.; Marken, F. Dalton Transactions 41 (2012) 1475
[2] Babu, K.F.; Kulandainathan, M.A.; Katsounaros, I.; Rassaei, L.; Burrows, A.D.; Raithby, P.R.; Marken, F. Electrochem. Commun. 12 (2010) 632.
[3] Halls, J.E.; Cummings, C.Y.; Ellis, J.; Keenan, L.L.; Jiang, D.M.; Burrows, A.D.; Marken, F. Molecular Crystals and Liquid Crystals 554 (2012) 12.
[4] Miles, D.O.; Jiang, D.; Burrows, A.D.; Halls, J.E.; Marken, F. Electrochemistry Communications (2012) http://dx.doi.org/10.1016/j.elecom.2012.10.039.

Heterogeneous Catalytic CO₂ Conversion

Designed with the environment in mind, our heterogeneous catalysts have been synthesised for the conversion of carbon dioxide (CO₂) to hydrocarbons. Our recent publications focused on the life cycle assessment and growth of carbon nanotubes on different supports has given us important information on the environmental impacts of our synthesis procedures [1] [2]. We have recently submitted a patent for the formation of an iron on carbon nanotube catalysts that is highly efficient for the conversion both CO₂ and CO to hydrocarbons [3].

Carbon nanotube-supported catalysts have been shown to be excellent for the conversion of CO₂ exhibiting low pressure drop which is very beneficial for efficient mass transfer to our catalyst particles on the surface of the nanotubes (see figure).

[1] D. R. Minett, J. P. O'Byrne, M. D. Jones, V. P. Ting, T. J. Mays and D. Mattia, Carbon, 2013, 51, 327-334.
[2] O.G. Griffiths, J.P. O’Byrne, L. Torrente-Murciano, M.D. Jones and D. Mattia, M.C. McManus, J. Cleaner Prod., DOI: 10.1016/j.jclepro.2012.10.040
[3] D. Mattia, M.D. Jones, J. P. O’Byrne, R. E. Owen, D. R. Minett, P. Plucinski, S. I. Pascu Patent Applied

Carbon capture and electricity production

The aim of this project is to use microorganism for capturing atmospheric CO₂. The produce biomass should then be used for the generation of electricity in microbial fuel cells.

The capture of carbon dioxide by photoautotrophs and the electricity production from algal biomass in MFC have been achieved separately during the first year. Since then, a new path has been investigated: the capture of carbon dioxide directly in the anodic compartment, were it is needed for electricity production. First results have shown that it is indeed possible to capture carbon dioxide and to have an electroactive mineralisation in the same anodic compartment. The actual work is now focused on improving the design of our MFC in order to have a stable current production over time from the carbon dioxide fixed in photoautotrophic biomass.

The BRL Team has already filed a patent on the core MFC technology (WO 2012/120314 A2), which is now published. Dr. Ioannis Ieropoulos appeared in the local Press with Dr. Julian Dennis (Wessex Water Director of Innovation and Research), 27 Nov 2012.

Dr. Ioannis Ieropoulos’s EcoBot work, which is directly related to the Carbon Capture project, was specifically mentioned by the Chancellor of the Exchequer, George Osbourne, in his address to the Royal Society, 9 Nov 2012.