Personal Biography

Michael Cotterell is an Associate Professor in Physical Chemistry and Tutorial Fellow in Chemistry at Corpus Christi College. Michael completed his undergraduate degree in Chemical Physics at the University of Bristol (2008-2012), where he remained to complete his PhD (2012-2016) under the supervision of Prof. Jonathan Reid and Prof. Andrew Orr-Ewing FRS. Michael then conducted postdoctoral research at the University of Exeter (2016-2019) with Prof. Jim Haywood, where he worked closely with Dr Justin Langridge at the Met Office to develop new laser-based spectroscopy instruments for in situ observations of aerosol particles in Earth’s atmosphere. During this time, he secured an Analytical Chemistry Trust Fund Tom West award to support his postdoctoral research. In 2019, he was awarded a NERC Independent Research Fellowship that allowed him to build his own research group at the University at Bristol. Michael took up his current position, at the University of Oxford and Corpus Christi College, in September 2023.

Research and Teaching

My physical chemistry research concerns laser-based spectroscopy of aerosol particles (mesoscale solid or liquid particles suspended in a gas, with particle diameters ranging from 10 nm to 100 µm) to improve our understanding of their optical, physical, and chemical properties. Applications of our research include: atmospheric aerosols and their impact on Earth’s climate; the potential for accelerated reactions in aerosols; the morphological properties and non-ideal mixing for internally mixed aerosol particles. To enable this work, we develop sensitive laser-based spectroscopy techniques for non-contact measurements of aerosol particles to provide new insights into their physicochemical properties. Excitingly, our group applies these spectroscopic techniques to study single, levitated aerosol particles, using laser beam optical traps or electrodynamic fields to levitate single particles. We also apply these techniques in the laboratory to study plumes of particles and collaborate closely with the Met Office on projects developing the next generation of instrumentation for in-situ aerosol observations

Selected Publications

M. I. Cotterell, J. W. Knight, J. P. Reid, A. J. Orr-Ewing, “Accurate Measurement of the Optical Properties of Single Aerosol Particles Using Cavity Ring-Down Spectroscopy”, Journal of Physical Chemistry A, 2022, doi:10.1021/acs.jpca.2c01246.

J. W. Knight, J. V. Egan, A. J. Orr-Ewing, and M. I. Cotterell, “Direct Spectroscopic Quantification of the Absorption and Scattering Properties for Single Aerosol Particles”, Journal of Physical Chemistry A, 2022, doi:acs.jpca.2c00532.

M. I. Cotterell, K. Szpek, D. A. Tiddeman, J. M. Haywood, and J. M. Langridge, “Photoacoustic Studies of Energy Transfer from Ozone Photoproducts to Bath Gases following Chappuis Band Photoexcitation”, Physical Chemistry Chemical Physics, 2021, doi:10.1039/D0CP05056C

B. R. Bzdek, J. P. Reid and M. I. Cotterell, “Open questions on the physical properties of aerosols”, Communications Chemistry, 2020, doi:10.1038/s42004-020-00342-9

M. I. Cotterell, K. Szpek, J. M. Haywood and J. M. Langridge, “Sensitivity and Accuracy of Refractive Index Retrievals from Measured Extinction and Absorption Cross Sections for Mobility-Selected Internally Mixed Light Absorbing Aerosols”, Aerosol Science and Technology, 2020, doi:10.1080/02786826.2020.1757034