PhD Chemistry (m/f/d)

Shaping change: this is what drives us at Forschungszentrum Jülich. As a member of the Helmholtz Association with some 7,600 employees, we conduct interdisciplinary research into a digitalized society, a climate‑friendly energy system, and a sustainable economy. We focus on the natural, life, and engineering sciences in the fields of information, energy, and bioeconomy. We combine this with expertise in high‑performance computing and artificial intelligence using unique scientific infrastructures.

We invite early‑career researchers to apply for a PhD position within the joint research project “TRANSFER – Training and Research Academy for Nuclear Safety and Future Expertise on Geological Repository Systems”. As part of a structured doctoral program, you will conduct research on cutting‑edge topics related to the disposal of high‑level radioactive waste. TRANSFER is jointly funded by the German Federal Ministry for Research, Technology and Space (BMFTR) and the Federal Company for Radioactive Waste Disposal (BGE) and is coordinated by the GFZ German Research Centre for Geosciences.

Activities and responsibilities

Carbonate minerals are present in many claystone formations and can contribute to the retention of radionuclides through co‑precipitation, surface reactions or the formation of solid solutions. The aim of this PhD project is to gain a comprehensive understanding of the retention of the radionuclides 226Ra and 90Sr in carbonate‑bearing claystones through a combination of experiments and simulations, and to elucidate the competition between sorption and co‑precipitation processes, as well as the reversibility of these processes. Furthermore, the effects of heterogeneities in the mineral composition and distribution on radionuclide migration in clay rocks will be evaluated. The findings will contribute to the improvement of process models for the cross‑scale description and simulation of radionuclide migration in the near‑ and far‑field of a geological repository for high‑level radioactive waste.

Your main responsibilities within the project will include

• Conducting sorption/desorption experiments to determine the retention of 226Ra and 90Sr in carbonate‑bearing claystones and its reversibility
• Conducting recrystallisation experiments to investigate the structural uptake of 226Ra into carbonate minerals
• Analysing selected samples from sorption and recrystallisation experiments using advanced analytical methods such as Raman spectroscopy, X‑ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and synchrotron‑based methods (µ‑XRF and µ‑XRD)
• Application of geochemical‑thermodynamic modelling to interpret the experiments
• Collaboration with modellers (reactive transport) to evaluate the migration behaviour of 226Ra and 90Sr in heterogeneous claystone formations across various spatial and temporal scales
• Presentation of results at scientific conferences and in peer‑reviewed publications

Qualification profile

• Master’s degree, diploma or equivalent in chemistry, radiogeochemistry, environmental chemistry, geochemistry, chemical engineering, mineralogy or related field
• Experience working in wet chemical laboratories
• Experience in geochemical or thermodynamic modelling is desirable
• Ability to work collaboratively within a multidisciplinary and international team
• Very good command of written and spoken English with extensive vocabulary is required (at least B2 level according to the CEFR), ideally supported by a certificate confirming the language level

Benefits

• A structured training programme: within the TRANSFER graduate school on geological disposal, comprising seminars, summer and winter schools, participation in conferences, and the opportunity for research stays at partner institutions, aiming at a comprehensive understanding of nuclear waste management
• Team & Environment: work in a motivated team with an international and interdisciplinary focus – at one of the largest research institutions in Europe
• Research & Infrastructure: access to excellent scientific and technical facilities for your work
• Networking & Exchange: participation in (international) conferences and project meetings and actively building your scientific network
• Supervision & Support: continuous, expert guidance from your academic supervisor
• Annual Leave: 30 days of annual leave
• Knowledge & Development: professional development support, e.g., through training and networking opportunities specifically for doctoral candidates (JuDocS)
• Health & well‑being: comprehensive company health management programme with options such as beach volleyball court, running groups, yoga classes and more; company medical service and experienced social counselling team available on site
• Campus experience: research campus in the countryside with collegial exchange and sporting activities on site; cafeteria offers a wide range of options – relaxing lunch break with a lake view
• Successful start: structured training for tasks and support from the very beginning with Welcome Days and Welcome Guide
• Fair remuneration: classification according to pay group 13 (75%) of the TVöD Bund; special payment (“Christmas bonus”); all information about the TVöD Bund collective agreement available on the BMI website (pay scale table on page 66 ff. of the PDF download)
• Support for international employees: International Advisory Service eases starting for international employees

In addition to exciting tasks and a collegial working environment, we offer you much more:

Diversity and inclusion

We welcome applications from people with diverse backgrounds, e.g. in terms of age, gender, disability, personal orientation/identity, and social, ethnic and religious origin. A diverse and inclusive working environment with equal opportunities in which everyone can realise their potential is important to us.

The following links provide further information on diversity and equal opportunities: and on specific support options: