Perovskite X/Gamma Detectors for Nuclear Security applications

The team at Surrey have worked for the last 5 years developing prototype perovskite radiation detectors. The bulk electronic properties of lead halide perovskites such as CsPbBr₃ and FAPbBr₃ have now improved to the point that they are suitable for high-quality gamma spectroscopy, with mobility-lifetime values similar to high-quality CZT. There is also clear evidence that the charge transport properties of solution-grown CsPbBr₃ and FAPbBr₃ are comparable to that of Bridgeman-grown CsPbBr₃ – either growth method has different advantages in terms of cost, material yield and speed, but the quality of the materials is very similar. Both CsPbBr₃ and FAPbBr₃ show good spectroscopic performance as gamma detectors.

This project will continue the recent work of Surrey students optimizing the crystal growth process to improve the crystallinity of the material. We have recently published results on an optimized perovskite growth process that uses a chemical additive DPSI (3‐decyldimethylammonio‐propane‐sulfonate salt) to grow high-quality FAPbBr₃ crystals with a low strain density and excellent charge transport properties. You will work on several key issues to improve the performance of perovskite radiation detectors, including strategies to improve the long-term stability of these devices and minimise electro-chemical degradation of the metal electrodes. 

The main objectives of the research will be as follows:

1. Growth of high-quality perovskite crystals using Surrey’s optimized solution growth method. You will make a quantitative study of defect concentrations in the crystals using Thermally Stimulated Current (TSC) measurements, and compare with Bridgman-grown CsPbBr₃.
2. Surface characterisation of interface regions to study the electrochemical reactions between perovskite and contact metal. Using facilities such as time-resolved PL and XPS depth profiling, you will study the metal halide distributions under the metal contact [Cha25]. 
3. Detector testing with radioisotopes – you will measure the spectroscopic performance and stability of FAPbBr₃ and CsPbBr₃ prototype detectors fabricated at Surrey, with the aim of significantly extending the device performance for stable operation for in excess of 6 months. 

You will be registered on the Surrey Physics PhD program, however you will be working within a multi-disciplinary research team at Surrey. You should have an interest in experimental research, ideally with experience of some aspects of radiation physics, nuclear physics, materials science or materials chemistry. The project will benefit from the excellent radiation physics and materials science facilities at Surrey, including gamma and X-ray spectroscopy, device fabrication, and crystal growth facilities. Additional characterisation methods are available in in Chemistry and Materials Science laboratories, for example Photoluminescence, Raman, Dynamic Light Scattering, SEM/TEM and XRD. 

We collaborate with a wide range of international partners, and there will be opportunities for you to travel to partner Universities for collaborative measurements during your PhD. For example, we work with Penn State University (USA) with access to their research nuclear reactor for detector tests, and we also partner with Bologna University (Italy) with the perovskite materials group. 

The project is funded by the RAPTOR Nuclear Skills doctoral focus award, with an enhanced stipend of £26,000 for a period of 4 years, starting from October 2026.

You will also collaborate with the Nuclear Threat Reduction network (NTRnet) with the opportunity to participate in NTRnet doctoral training events. 

Please contact Paul Sellin for further information or for an informal discussion about this project.

Open to candidates who pay UK/home rate fees. See UKCISA for further information.

You will need to meet the minimum entry requirements for our PhD programme.