Development of Radiation Detectors using Semiconductor Perovskite Materials.

1) Brief description of the context of the research including potential impact:
Radiation detectors used in security and medical contexts are made using materials sensitive to ionisation radiation that produce light or an electrical charge that can be gathered to create meaningful data such as a diagnostic x-ray image. Recent studies of perovskite materials have highlighted their potential for x-ray detection due to their high absorption coefficients, excellent electrical properties and relatively low cost of production among other things.

This study will further investigate these properties in order to develop a 3D printable radiation detector using perovskite materials. Such a detector would be beneficial in environments where simple, robust radiation detectors could be used for security purposes, e.g. monitoring ionising radiation at ports or in a tunnel. The future could also see 3D printable detectors applied in fields such as radiotherapy where patient-specific detectors may be desirable.

2) Aims and Objectives:
The ultimate objective of this project is to lay the foundations for a functioning radiation detector made using perovskite material such as CsPbBr3 that is scalable, easily producible and made with low-cost materials. We aim to develop a 3D printable radiation detector by investigating the practicality of a conductive material that has been loaded with radiosensitive perovskite material.

In particular, we are exploring the use of FDM 3D printing with a filament that is both conductive and will produce an electric current in the presence of ionising radiation. We hope to do this by adding perovskite material that has been synthesised in a lab to the carbon-loaded conductive filaments commercially available for 3D printing.
We will be working with the University of Surrey to produce perovskite-containing conductive filaments and to extensively characterise their properties. These filaments will later be used for 3D printing methods in order to produce a device capable of radiation detection.

Additional work may include Monte Carlo simulations that can help characterise the sensitivity of Perovskite-based radiation detectors.

3) Novelty of Research Methodology:
This study will include experimental and simulation methodologies. Experimental components will come from the development of perovskite materials and combining these with 3D printable filaments. It will also include experiments for characterising the materials produced.
Possible simulation work will involve calculations of dose deposited into the perovskite-loaded material as we assess the material's radiation detecting capabilities.

4) Alignment to STFC's strategies and research areas:
STFC supports research in physics and materials science and this study will expand our knowledge of perovskite materials and their real-world security and medical applications.

5) Any companies or collaborators involved:
This PhD studentship has been funded by NuSec (Nuclear Security Science Network). We will be collaborating with the University of Surrey, who will be allowing us access to their laboratory for the purposes of Perovskite synthesis, as well as some of their custom material characterisation setups.

Maximising impact is at the heart of the NuSec network, through the use of a range of funded impact activities that lie at the heart of the network's objectives. In this extension proposal we will continue to identify pathways to impact across the broad range of network activities.

Here we describe the wider impact that the NuSec network has achieved during Phase 1, and will continue to deliver in Phase 2.

1. The Beneficiaries
(i) Society - the nuclear security agenda is critical to national safeguarding and to the protection of society. A strong engagement between government agencies, academic and industry generates a benefit for all of society. A good example from Phase 1 of the network was our NuSec workshop on alternative technologies for the oil well logging industry. This brought together ~30 senior oil industry experts from Europe and US for a 2 day workshop at the Institute for Advanced Studies at Cambridge University.
(ii) People - the network continues to provide cross-fertilisation of technical expertise between research disciplines and the integration of the various stakeholder communities. Those engaging with the network extend their skills set and experience. The network offers grants to support a wide range of professional and researcher development skills, and to provide technical training opportunities to benefit researchers.

2. How the Network Activities will deliver Impact
The network delivers impact directly through its programme of regular and occasional activities.

Developing Strategic Partnerships
The network's primary objective has been to establish a forum for discussion and collaboration between the academic, industrial and defence sectors. This has accelerated the development of a strong research community in the nuclear science area, and has acted to broker interactions and partnership between the academic and MoD/Home Office communities. Our strategic partners each offer a unique input into the programme and are fully involved with the regular network meetings and technical workshops. Both the network's Management Group (MG) and End User Panel (EUP) are made up of key stakeholders who monitor the network's progress towards developing strategic partnerships. The independent Steering Board, representing the interests of the stakeholder groups, ensures the development of partnerships through these various activities.

Technology Development
The network will continue to receive direct funding from AWE to support pilot studies and small proof of concept studies. These are challenge-led projects that are focussed on the requirements of these government agency stakeholders. In this way the network develops technology demonstrators that address government requirements, for example as defined by the national counter terrorism strategy CONTEST which addresses the "...highest impact terrorist risks including even nuclear materials..." In Phase 1 of the network, NuSec awarded 15 of these pilot projects to UK Universities, which addresses technical challenges identified by the End Use Panel.

Dissemination activities
All network outputs are unclassified, and the majority are publicly available and openly disseminated, including technical workshop presentations, results from pilot studies, scoping documents and position papers. Dissemination uses a dedicated website to promote the network activities and outputs, and the University's Surrey Research Insight digital open access repository to store and disseminate network outputs and documents. The network showcase meeting will publicise the network outputs to a wider audience.

Supporting Researcher Engagement: The network will provide a series of opportunities for researchers to develop their technical skills and knowledge.

Full details are given in the separate Pathways to Impact Statement