Scheme: Wolfson Research Merit Awards
Organisation: Cardiff University
Dates: Sep 2014-Aug 2019
Summary: Free radical reactions and redox processes are ubiquitous in nature and indeed fundamental to life. These radicals are present in the air we breath, the food and drinks we consume, and in the many substances we use on a daily basis. Whilst many free radical mediated reactions can produce unwanted side-effects in their surroundings, on the other hand several essential redox processes occurring in our bodies actually rely on the participation of free radicals, while the hydroxyl radical acts as the primary ‘cleaning agent’ in the Earths lower atmosphere. In Chemistry, numerous chemical transformations are actually dependent on the participation of radicals and paramagnetic species, particularly in Catalysis. Despite their importance and abundance, the role of these radicals is exceedingly complex and remains poorly understood. For this reason, coupled with their very short lifetimes, they remain intriguing and elusive entities to study, presenting a real experimental challenge to trap and potentially control such highly reactive & short-lived species. My research has focused on the study and characterization of free radical and paramagnetic species primarily those involved in catalysis using Electron Paramagnetic Resonance (EPR) spectroscopy. Through the Wolfson Research Merit Award, I am developing a new approach to stabilize the exotic and short lived species using fast pressurized capabilities in combination with EPR spectroscopy. Rapid changes in pressure (a Pressure Jump) can generate non-equilibrium conditions in the catalytic reaction medium; pressure, as an important thermodynamic driver, alters not only the radical kinetics of the catalytic reaction, but also the structure and shape of the catalyst itself. This PJ-EPR approach is providing a unique insight into the catalytic chemistry of radical centres, and this information is vitally important not only in catalysis but in many chemical transformations and biological processes.