PhD Studentship - Harnessing Nature’s CO2 Catalyst to Accelerate Marine Carbon Dioxide Removal

Harnessing nature’s CO2 catalyst to accelerate marine carbon dioxide removal – PhD Ref: 6085

Supervisors

Professor Nicholas Harmer, University of Exeter, Department of Biosciences

Professor Rod Wilson, University of Exeter, Department of Biosciences

Professor Paul Halloran, University of Exeter, Department of Geography

Could biology help us engineer a new way of removing carbon dioxide from the atmosphere?

Achieving carbon dioxide removal (CDR) at enormous scale is likely to be an important part of tackling climate change. The ocean naturally exchanges CO₂ with the air, but because the alkalinity of that seawater buffers CO₂, the amount of carbon dissolved in the ocean is vastly greater than in the atmosphere. For context, if you took all the CO₂ that humanity has every emitted and stirred it into the ocean, the seawater carbon concentration would only increase by about 2%.

An extremely promising technique, known as Ocean Alkalinity Enhancement, aims to increase the buffering of CO₂ by seawater. This would allow seawater to take up even more atmospheric CO₂, helping us to balance the emissions from activities - such as flying and farming - that we don’t know how to decarbonise, and potentially even begin to reverse climate change.

But there is a fundamental problem.

Transferring atmospheric CO₂ into that seawater is slow. This means that CO₂ uptake happens over tens to hundreds of kilometres downstream of where a carbon removal facility may be, with implications around marine ecosystem impacts, scalability, verification and cost. If this exchange could be dramatically accelerated, it could open the door to a different approach to marine carbon dioxide removal.

This PhD, part of the CASE4CDR project which is aligned with ARIA’s Resilient Climate and Ecosystems Opportunity Space, will explore whether harnessing biology can allow us to overcome this problem.

Carbonic anhydrases catalyse the conversion between carbon dioxide and bicarbonate, speeding up the reaction by up to 10 million times. These enzymes are found in almost all living organisms, and we will work with you to isolate and stabilise them, utilising the same chemistry that operates in your body and in marine organisms to overcome the reaction bottleneck and rapidly convert carbon dioxide and water into ocean bicarbonate. The project will give you the opportunity to learn advanced skills in enzymology, structural work, and protein chemistry to develop these enzymes to meet the environmental challenge. It will also involve small lab-scale tests to quantify the efficacy of atmospheric CO₂ absorption by alkalinity-enhanced seawater using immobilised enzymes.

You will work closely with a parallel PhD researcher working on larger-scale CO₂ exchange and measurement.

From laboratory experiments to the sea

A particularly exciting feature of this PhD is that, with the right safeguards in place, the work is intended to move beyond laboratory proof-of-concept.

Upon meeting key acceptance criteria, you will help translate fundamental measurements and engineering designs into trials using real seawater at the SeaCURE pilot facility situated on the coast near Weymouth.

This will create a unique opportunity to follow an emerging climate technology through multiple stages of development: from calculations and controlled laboratory experiments, through engineering and instrumentation, to operation in a real marine environment.

Carbon dioxide removal cannot succeed on engineering performance alone.

You will join a wider interdisciplinary project examining what would actually be required to deploy a new marine carbon removal technology responsibly. Alongside your core research, you will have opportunities to contribute to work around environmental permitting, regulation, environmental impacts, public and stakeholder engagement, and trials at the Weymouth plant.

That wider perspective is important. The central question is not just can we build it, but can we develop a carbon-removal system that is measurable, environmentally responsible, socially acceptable and capable of eventually operating at meaningful scale.

What are we looking for?

The project would particularly suit someone who enjoys working at pace, building things and solving quantitative problems, but also zooming out from the lab scale to understand the real word social, political and practical deployment opportunities and constraints around Carbon Dioxide Removal. You might come from biosciences, chemistry, environmental science, or another quantitative discipline.

What matters most is enthusiasm for rigorous experimental science and problem solving, and being powerfully motivated by working on one of the defining problems of our time.

The University of Exeter is inviting applications for a PhD studentship, aligned with ARIA’s Resilient Climate and Ecosystems Opportunity Space, to commence on 4 January 2027 or as soon as possible thereafter. For eligible students the studentship will cover Home tuition fees plus an annual tax-free stipend of at least £21,805 for 3.5 years full-time, or pro rata for part-time study. The student would be based in the Living Systems Institute in the Faculty of Health and Life Sciences at the Streatham Campus in Exeter.

International students who wish to apply for this opportunity will need to be in the UK ahead of the programme start date on 4 January 2027, so will need to ensure they have any student visas (if applicable) and ATAS clearance in place ahead of this date. Students who pay international tuition fees are eligible to apply, but the award will only cover part of the international fees (approximately £27,000). The international fee in 2026/27 is £28,900 and will increase in 27/28.

International applicants will need to cover additional costs, including:

• Student visa fees
• Immigration Health Surcharge
• Relocation expenses associated with moving to the UK to undertake the PhD.

International fee-paying applicants should ensure they have sufficient funds to meet these costs before applying.

The conditions for eligibility of home fees status are complex and you will need to seek advice if you have moved to or from the UK (or Republic of Ireland) within the past 3 years or have applied for settled status under the EU Settlement Scheme.

The collaboration involves a project partner who is providing funding and other material support to the project, this means there may be special terms that apply to the project, these will be discussed with candidates at interview and fully set out in the offer letter. The collaboration with the named project partner is subject to contract. Please note full details of the project partner’s contribution and involvement with the project is still to be confirmed and may change during the course of contract negotiations. Full details will be confirmed at offer stage.

Entry requirements

Applicants for this studentship must have obtained, or be about to obtain, a First or Upper Second Class UK Honours degree, or the equivalent qualifications gained outside the UK, in an appropriate area of quantitative sciences such as biological sciences, chemistry, or environmental sciences.

If English is not your first language you will need to meet the English language requirements and provide proof of proficiency. Click here for more information.

How to apply

To apply, please click the ‘Apply Now’ button above. In the application process you will be asked to upload several documents:

• CV
• Letter of application (outlining your academic interests, prior research experience and reasons for wishing to undertake the project).
• Transcript(s) giving full details of subjects studied and grades/marks obtained (this should be an interim transcript if you are still studying)
• Two references from referees familiar with your academic work. If your referees prefer, they can email the reference direct to PGRApplicants@exeter.ac.uk quoting the studentship reference number.
• If you are not a national of a majority English-speaking country you will need to submit evidence of your proficiency in English.

The closing date for applications is midnight on 26th November 2026. Interviews will be held virtually or on the University of Exeter Streatham Campus in the week commencing TBC.

All application documents must be submitted in English. Certified translated copies of academic qualifications must also be provided.

Please quote reference 6085 on your application and in any correspondence about this studentship.

Summary