Project highlights

  • Assessment of the electrocatalytic properties of naturally-occurring minerals 
  • Synthesis of Nature-inspired mineral electrocatalysts for technologically important reactions 
  • Production of photochemical devices for green technology applications such as hydrogen production and CO2 sequestration 

Overview

In order to limit global warming to no more than 1.5 °C, as dictated by the Paris Agreement, it is imperative that global carbon emissions reach net zero by 2050. In a world that shows few signs of curbing appetites for energy consumption, new technological solutions are required to both produce cleaner, carbon-free energy and to actively sequester atmospheric carbon dioxide.  

Hydrogen has great promise as a feedstock fuel for future sustainable energy technologies, with H2-powered transport already in use. At present, however, the majority of H2 produced globally is derived from limited carbon-based fuels and therefore contributes to global carbon emissions. Efficient production of H2 using catalysts based around cheap, robust, and sustainable catalysts therefore represents a major challenge. A number of bio-inspired catalysts have been reported based around naturally-occurring minerals. A variety of chalcogenides (S, Se, or Te-containing minerals) have structures that are very similar to the active site of enzymes capable of a number of electrocatalytic reactions, including H2 production and CO2 reduction. The enzymes themselves are unlikely to be technologically practical from an economic perspective, so in this project we aim to ‘reverse engineer’ enzyme functionality into both natural minerals, and synthetic inorganic materials based on natural mineral structures, in a novel approach to bio-inspired inorganic geochemistry. 

Deep eutectic solvents, which can be thought of as a specific class of ionic liquid, represent low-toxicity, cheap, and reusable media for synthesis of metal sulfide materials. In this project you will explore the production of ‘artificial’ minerals in deep eutectic solvents, and characterise their performance as electrocatalysts and in photochemical devices. You will investigate methods for one-pot and post-synthesis introduction of catalytic amino acids and prosthetic groups inspired by the active site structure of enzymes, and use these to fine-tune catalyst performance. Both ‘native’ and ‘non-native’ reactivity will be explored, in order to unlock new synthetic chemistry from ancient and affordable metal sources. 

A graphical representation of an active site of a chemical structure.

Figure 1: Metalloenzymes contain active sites with structures very similar to naturally-occurring minerals. For example, [NiFe] hydrogenase active site architecture is remarkably similar to the mixed Ni-Fe chalcogenide pentlandite. 

Host

University of Leicester

Theme

  • Climate and Environmental Sustainability

Supervisors

Project investigator

Co-investigators

How to apply

Methodology

Initial synthetic work will exploit novel synthetic methodologies developed in Leicester to produce mixed sulfide alloys of metals such as Ni, Fe, Co, and Mo, which are present in naturally-occurring enzyme catalysts. Sample structures will be characterised by methods including X-ray diffraction, atomic force microscopy, transmission electron microscopy, X-ray photoelectron spectrometry, Raman and infrared spectroscopy. Electrocatalytic performance will be characterised using gas chromatography, rotating disc and rotating ring disc electrochemistry, and electrochemical impedance spectroscopy. Existing collaborations of Ash at national facilities such as Diamond Light Source will be used to carry out further advanced in situ characterisation.  

Training and skills

DRs will be awarded CENTA Training Credits (CTCs) for participation in CENTA-provided and ‘free choice’ external training. One CTC can be earned per 3 hours training, and DRs must accrue 100 CTCs across the three and a half years of their PhD.  

Training will be provided in a broad range of interdisciplinary skills encompassing synthetic and analytical methods, including infrared (IR) spectroscopy, X-ray spectroscopy, electrochemistry, and Gas Chromatography. There will be opportunities for travel to national and international facilities to undertake experimental work, notably Diamond Light Source and the Central Laser Facility (UK), and MAX-IV (Sweden). The successful candidate will be encouraged to present their work at a range of international conferences throughout the course of the PhD. 

Further details

Potential applicants are welcome to discuss the project informally with the project supervisors: Dr Philip Ash ([email protected]) and Dr Patricia Rodriguez Macia (email: [email protected]).  

More information about the supervisory team and the School of Chemistry at the University of Leicester can be found here: https://le.ac.uk/chemistry; https://www.rodriguezmacialab.com/ 

To apply to this project:  

  • You must include a CV with the names of at least two referees (preferably three) who can comment on your academic abilities.  
  • Please submit your application and complete the host institution application process via: CENTA PhD Studentships | Postgraduate research | University of Leicester.  Please scroll to the bottom of the page and click on the “Apply Now” button.  The “How to apply” tab at the bottom of the page gives instructions on how to submit your completed CENTA Studentship Application Form 2025, your CV and your other supporting documents to your University of Leicester application. Please quote CENTA 2025-L1  when completing the application form.  

Applications must be submitted by 23:59 GMT on Wednesday 8th January 2025.  

Possible timeline

Year 1

Synthesis of novel mineral materials, structural, physical and chemical comparison with natural minerals. Synchrotron beamtime 1.

Year 2

Test scope of electrocatalytic properties of synthetic and natural minerals. Modify the mineral surfaces to produce new bio-hybrid catalysts. Synchrotron beamtime 2. 

Year 3

Develop photocatalytic systems and photochemical devices based on the most promising materials. Synchrotron beamtime 3. 

Further reading

McPherson, I. J., Ash, P. A. et al. (2017) ‘Electrochemical CO Oxidation at Platinum on Carbon Studied through Analysis of Anomalous in Situ IR Spectra’, Journal of Physical Chemistry C , 121, pp. 17176-17187, https://doi.org/10.1021/acs.jpcc.7b02166. 

Ash, P. A. et al. (2017) ‘Proton Transfer in the Catalytic Cycle of [NiFe] Hydrogenases: Insight from Vibrational Spectroscopy’, ACS Catalysis, 7, 4, pp. 2471-2485, https://doi.org/10.1021/acscatal.6b03182. 

Yang, C., Gao, M. Y., Zhang, Q. B., Zeng, J. R., Li, X. T., Abbott, A. P. (2017) ‘In-situ activation of self-supported 3D hierarchically porous Ni3S2 films grown on nanoporous copper as excellent pH-universal electrocatalysts for hydrogen evolution reaction’, Nano Energy, 36, 85-94, https://doi.org/10.1016/j.nanoen.2017.04.032. 

Konkena, B., junge Puring, K., Sinev, I. et al. (2016) ‘Pentlandite rocks as sustainable and stable efficient electrocatalysts for hydrogen generation’ Nat Commun 7, 12269, https://doi.org/10.1038/ncomms12269 .