Supramolecular building blocks for carbon capture materials

"This is a PhD research project in Chemistry.

The UK has a target of reducing net carbon emissions to zero by 2050. To achieve this challenging target, several difficult technological challenges need to be overcome before fully renewable energy sources can be adopted. As this transition will likely take time, capturing and storing the carbon released from fossil fuel consumption will play an important role in meeting the targeted reduction in achieving net-zero emissions. Materials which are capable of capturing CO2 at low concentrations (direct air capture) are not widely available due to the challenges faced with selective absorbing the % of CO2 from the atmosphere. There are also challenges associated with the recycling of the capture materials once the CO2 has been safely stored. Typically, these materials require an energy intensive heating cycle to be regenerated, offsetting the carbon capture process.
Supramolecular chemistry offers one of the more viable routes to carbon capture, and framework materials such as MOFs have been widely studied. Less studied molecules (in this context) include calixarenes and pillarenes, both of which contain an inherent cavity. These compounds can be synthesised on a large scale from cheap starting materials and can be readily functionalised at different regions to tune their reactivity or immobilise the molecule by binding a wide range of surfaces. Exploiting this feature, this project aims to utilise targeted functional groups to reversibly trap CO2, a key step in the carbon capture and storage process. As the reaction is selective for CO2 it would have the potential to remain effective even in low concentrations (e.g. direct air capture systems), and over multiple capture/release cycles. The major advantage of this chemistry is that the compounds are all relatively low cost, can be produced in large quantities and offer vast scope for optimisation. self-assembly is controlled by a cheap, non-toxic gas and it is possible to cycle between the two states multiple times.
The project is interdisciplinary and will involve optimising chemical syntheses using established reactions before moving on to explore new transformations. Analysis will be performed using a range of techniques as appropriate (NMR, MS, XRD, IR, UV-vis etc). Doctoral studies will be supported through a range of subject-specific training opportunities, significantly enhancing the postgraduate experience and employment potential as a result. HWU also has excellent training courses for PGRs (run by the Research Futures Academy) that enhance transferrable skills and include topics such as applying for funding. Finally, the studentship will be further supported by Sasol Chemicals Advanced Materials division via the contribution of samples, material analysis, and technical expertise in high porosity alumina supports."