Non-linear dynamics and Turing pattern formation in electrocatalytic reactions
When far from equilibrium, and in the presence of the adequate feedback mechanism, both homogeneous and heterogeneous reactions can exhibit bistable or oscillatory behavior, associated with spatial self-organization. These non-linear-dynamics phenomena are characteristic of any open system far from equilibrium, and their relevance goes beyond the limits of Physics and Chemistry. Temporal and spatial pattern formation is also usual in electrochemical reactions, but, while in purely chemical systems the feedback mechanism reduces to an interaction between the reaction kinetics and transport phenomena, in electrochemical systems it also includes the electrical circuit. Furthermore, it has been shown that the efficiency of a fuel cell can be higher when operated under oscillatory conditions. This makes the deep understanding of non-linear dynamics of electrocatalytic reactions also relevant from a technological point of view. In the case of homogeneous systems, concentration patterns are often easy to visualize due to the associated color changes, and in ultrahigh vacuum (UHV) photoemission electron microscopy can be used to observe the evolution of reaction fronts on the catalyst surface. In electrochemical systems, the presence of the electrolyte has limited the development of techniques that can provide a time-resolved sequence of bidimensional images of the electrode surface with which temporal and spatial pattern formation can be studied.
The objectives of this PhD project are: (i) to demonstrate the ability of optical reflectance microscopy to study pattern formation on electrode surfaces during the oxidation of CO in the bistable region and during the oxidation of formic acid in the oscillatory regime; (ii) to visualize, using optical reflectance microscopy, complex cooperative behavior in microelectrode arrays (e.g., synchronization of individual oscillators or development of a hierarchical order) under non-equilibrium conditions; and (iii) to develop mathematical models that can predict the observed patterns and lead to a deeper understanding of the involved processes.
The successful candidate should have, or expect to have an Honours Degree in Chemistry or Physics at 2.1 or above (or equivalent)
There is no funding attached to this project, it is for self-funded students only.
Formal applications can be completed online: http://www.abdn.ac.uk/postgraduate/apply. You should apply for PhD in Chemistry, to ensure that your application is passed to the correct College for processing. Please ensure that you quote the project title and supervisor on the application form.
Informal inquiries can be made to Dr A Cuesta Ciscar, ([email protected]) with a copy of your curriculum vitae and cover letter. All general enquiries should be directed to the Graduate School Admissions Unit ([email protected]).