Resorcinol-formaldehyde (RF) gels are widely used in industry and on the laboratory scale to produce materials for a variety of applications in energy and nanomaterials. The opaque 'native' gels demonstrate high physical strength and low thermal conduction making them ideal as insulators and for use in optical and electrical systems. However, RF gels are more often pyrolised (heated in inert atmosphere, e.g. nitrogen) to produce porous carbons, which can be further activated by heating in active gas streams. Such carbons have wide application in filter technologies, gas separation/storage, water purification, catalysis and capacitors.

Despite wide application, current manufacture is typically by trial and error processes, as neither nanoscale assembly processes nor factors controlling physical properties of final gels are fully understood; acceptance of less than optimal materials is common. Due to lack of control and understanding on the bench scale, industrial scale up leads to additional issues such as increased gelation times and changes in physical characteristics. Researchers and industrialists frequently produce gels that could be greatly improved by greater understanding of nucleation, self-assembly and gelation processes. Proper understanding would allow rational design, in turn enabling both enhanced performance of existing materials and novel bespoke products for applications requiring precise control of gel properties such as pore sizes, e.g. for selective storage and delivery, filtration.

This project focuses on improving our understanding of factors affecting gel formation by producing a 'design tool' allowing selection and production of RF gels with required properties. We will study nucleation and assembly processes leading to gelation by combining experiment and computer modelling. The role of specific factors (e.g. pH; total solids content; catalyst, resorcinol, formaldehyde, water contents; gelation temperature) will be determined and quantified, enabling control of end properties through setting recipe and process parameters. This will improve quality of current materials as well as open up novel applications through better control of characteristics. To probe and understand gelation stages and properties of end products we will compare structural analysis of computer models of gelation (Monte Carlo, diffusion limited and cluster-cluster aggregation models, percolation and scaling theories etc.) with experimentally synthesised RF gels and subsequently carbonised gels, varying the above factors. Dr Mulheran's proven track record in simulation of nucleation will underpin the unique aspect of this study, providing a model to design tailor-made materials, while Dr Fletcher will provide expertise in gel synthesis and physical characterisation methods to produce data required to develop the model. Access to the Faculty's High Performance Computing facilities will be required and supported by Dr Mulheran's expertise, a co-investigator on the ARCHIE WEST programme. Uniting experimental and theoretical methods, enables us to take full advantage of expertise within CPE. The project also involves development of international collaborations with ETH Zurich (X-ray measurement of porous structures), Dusseldorf University (structural analysis of complex porous materials and particulates) and Liege University (scaled-up manufacture).

Resources required include chemicals (for gel manufacture/analysis), lab sundries (glassware, adsorption consumables) and software. After initial desktop-scale development, modelling will make use of Faculty High Performance Computing facilities.