Research
Bifunctional electrocatalysts for oxygen evolution and reduction reactions
Principal investigator: | Ana JORGE SOBRIDO |
The search for green alternative sources of energy is of great importance for our current society. In order to battle increasing greenhouse gases and global warming created by the use of fossil fuels, and to meet the UK's 2050 climate change targets, we need to develop new technologies that allow researchers to tackle this problem. Some of these alternatives include fuel cells, solar cells, batteries, supercapacitors and water electrolysers. OER and ORR are key processes taking place in most of these technologies and will be the focus of this project. The high cost of the noble metal catalysts employed in energy conversion and storage devices is one of the major drawbacks to their full development and exploitation. There are many reports new materials that can overcome state-of-the-art limitations at an acceptable cost. However, not much research has been done to understand the effect of nanostructuring, hybridisation between various electrochemically active materials and understanding the structure-property relationships to allow an improved performance.
In this project, I will design hybrid materials combining already known transition metal perovskite electrocatalysts with nitrogen-doped carbons electrocatalysts using the electrospinning technique. These new hybrid nanostructures will be characterised using state-of-the-art techniques. I will also design in operando studies combining structural and property coupled measurements. The electrocatalytic activity of perovskites is thought to be due to the presence of oxygen vacancies in their structure. By combining Raman spectroscopy and OER and ORR measurements, we will be able to monitor the changes in the oxygen vacancies of the perovskites (detected by Raman spectroscopy) as their electrochemical performance is evaluated. A similar approach will be developed using X-ray computed tomography, which will provide invaluable information about the complex structures and interactions involved in the catalytic process at the different structural levels of organisation and integrated within real devices. This will be correlated with the electrocatalytic activity of N-doped carbon materials studied by X-Ray Adsorption studies and the synergy between these two electrocatalysts understood. This will lead to a better understanding of the parameters influencing the activity of these materials in relation to their structure and also to the device environment and will facilitate a better electrode engineering.
This project will be conducted at the Materials Research Institute (MRI), Queen Mary University of London (QMUL). The MRI brings together a range of expertise with different schools including Engineering and Materials, Physics and Astronomy, Biological and Chemical Sciences, and Dentistry, providing a platform to support interdisciplinary materials research. I maintain a close collaboration with the Electrochemical Innovation Lab (Chemical Engineering Department, UCL) which will provide access to X-ray computed tomography and industrial links to test the new materials at scaled-up dimensions. Coupled structure-property studies will be carried out in collaboration with Dr. Ozlem Sel and Dr. Ivan Lucas, from Laboratoire Interfaces Systemes Electrochimiques (LISE, CNRS, Paris, Sorbonne Universites). An internal collaboration with Prof. Titirici group at MRI-QMUL working on N-doped carbon electrocatalysis will complement these collaborations.