Understanding and Improving Electrochemical Carbon Dioxide Capture

This transformative research fellowship will advance electrochemical carbon dioxide capture as a greenhouse gas mitigation technology. To limit global warming to 1.5C and avoid catastrophic climate change we must greatly reduce our emissions of greenhouse gases. To this end the UK has recently committed to net zero greenhouse gas emissions by the year 2050. Carbon dioxide capture and storage (CCS) is a critical technology that must be deployed at scale if the UK is to meet this goal. CCS is a process where carbon dioxide is first captured at point sources (industrial processes, fossil fuel power) or directly from the atmosphere, before subsequently being stored underground. State of the art CCS technology uses amine molecules to absorb carbon dioxide. Subsequently a large amount of energy must be supplied in the form of heat (or a vacuum) to regenerate the amines and release pure carbon dioxide for storage, thereby increasing the cost of CCS. The amine process also suffers from (i) limited carbon dioxide capacities, (ii) amine evaporation into the atmosphere and (iii) amine degradation in the presence of oxygen and other contaminant gases. This programme will explore the use of electricity to capture and release carbon dioxide as a more energy-efficient method of CCS that can overcome the limitations of amines. In electrochemical carbon dioxide capture, the charging of an energy storage device such as a battery or a supercapacitor causes the selective absorption of carbon dioxide. When the device is discharged, pure carbon dioxide is released (for subsequent storage), and much of the energy supplied during charging is recovered. Initial work suggests that this technology may be more energy-efficient than existing approaches, and there is still vast room for improvement, especially if the molecular mechanisms of capture can be understood and manipulated. We will (i) advance the understanding of electrochemical carbon dioxide capture and (ii) discover new materials and devices that capture carbon dioxide more efficiently. Specifically we will focus on electrochemical carbon dioxide capture by (i) supercapacitors and (ii) batteries. We will measure the amount of carbon dioxide that can be captured by these devices and we will vary the structures of the materials used to guide their improvement. A proper understanding of the molecular mechanism of electrochemical carbon dioxide capture may lead to breakthroughs for this technology. A key thrust of the programme is therefore mechanistic studies of the molecular-level capture mechanism. We will use a suite of experimental techniques to study the chemical structures of the electrode materials, and we will correlate these structures with their carbon capture properties. We will develop nuclear magnetic resonance studies that allow the molecular form of the bound carbon dioxide to be determined at different stages of the capture process. Our mechanistic studies will inform the design and synthesis of improved materials for electrochemical carbon dioxide capture. We will synthesise the next generation of materials with (i) larger carbon dioxide uptake capacities, (ii) lower energy requirements for regeneration and (iii) faster uptake rates. New technology generated by this work will be prototyped and developed into new products. The developed technology will generate clean economic growth and will help the UK meet its 2050 net-zero emissions target. The research background of ACF combined with the assembled team of partners and excellent institutional support will lead to new knowledge and technology that will make the UK world-leading in electrochemical carbon dioxide capture.