Photocatalysis supported by non-innocent ligands

Photocatalysis allows light energy to be harnessed to drive catalytic reactions via single-electron transfer. However, many redox-catalytic processes, including those that involve oxygen atom transfer, require the transfer of more than one electron.1

The aim of this project is to use photo-induced electron transfer to remove two electrons from a catalytic centre to enable the two-electron oxidation of a substrate.
The key to this approach is the combination of a redox-active ligand, a so-called non-innocent ligand, with a redox-active metal centre to form the catalytic unit (Figure 1).

Redox non-innocent ligands play a crucial role in the mechanism of catalytic processes, including those that catalyse the removal of two electrons. By modelling the active centre of metalloenzymes, we have recently discovered a new way of metal-ligand cooperation, which is based on a reversible reaction that involves the oxidation/reduction of a coordinated ligand. The ligand-centred reaction alleviates the charge build-up at the metal centre during the rate-determining step of the catalytic cycle, thereby enhancing the overall reaction rate.1, 2 Since the ligand oxidation can be triggered by photochemically, these systems are of interest for further development as electron relays in multielectron photocatalysis. The challenge is to achieve the light-driven oxygenation of biochemically or industrially relevant substrates, ensuring that both the oxidised and reduced products are useful.

Applicants should hold (or expect to be awarded) a first class or upper-second class Masters degree or equivalent in Chemistry and have a background that includes synthetic chemistry and catalysis.

All research students follow our innovative Doctoral Training in Chemistry (iDTC): cohort-based training to support the development of scientific, transferable and employability skills. All research students take the core training package which provides both a grounding in the skills required for their research, and transferable skills to enhance employability opportunities following graduation. Core training is progressive and takes place at appropriate points throughout a student’s higher degree programme, with the majority of training taking place in Year 1. In conjunction with the Core training, students, in consultation with their supervisor(s), select training related to the area of their research.

The project is multi-disciplinary and involves a variety of techniques, ranging from organic ligand synthesis through to metal-complex formation and characterisation, photocatalysis and spectroscopy (NMR, IR, UV/vis and EPR). Full training for postgraduate students, tailored to their particular degree background, will be provided within each research group. The successful applicant will be part of the departmental iDTC, which offers a range of relevant training courses, including courses on scientific writing and presentation skills (see above). In addition, the appointed candidate will participate in regular inorganic chemistry group meetings and will have the opportunity to attend at least two conferences.

Shortlisting will take place as soon as possible after the closing date and successful applicants will be notified promptly. Shortlisted applicants will be invited for an interview to take place at the University of York on either the 13 or 15 February 2018. Candidates will be asked to give a short presentation prior to their interview by an academic panel.

The Department of Chemistry holds an Athena SWAN Gold Award and is committed to supporting equality and diversity for all staff and students. This PhD project is available to study full-time or part-time (50%).