Metal-Halide Perovskites as Innovative and Cost-Effective Fluoride Salt Waste Forms

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Troy, New York
Project Term:
04/22/2022 - 10/21/2024

Critical Need:

The next generation of advanced nuclear reactors (ARs) is currently being developed to enhance the safety, reduce the cost, and increase the efficiency of nuclear power generation, which is important to meeting greenhouse gas (GHG) emission goals. Challenges associated with disposal pathways of waste, such as used nuclear fuel (UNF), however, threaten AR development and deployment. ONWARDS seeks to develop and demonstrate breakthrough technologies that will facilitate a 10x reduction in AR waste volume generation or repository footprint. In addition, ONWARDS aims to advance development of high-performance AR waste forms while maintaining exemplary safeguards standards and global back-end costs in the accepted range of $1/megawatt-hour.

Project Innovation + Advantages:

Rensselaer Polytechnic Institute (RPI) will explore using inorganic metal halide perovskites (MHPs) as advanced salt waste forms to immobilize fluoride-based salt wastes from advanced reactors. The RPI team will demonstrate low-temperature wet-chemistry processes to effectively separate fluoride salt wastes at temperatures lower than 200oC and reduce the waste volume of alkali and alkaline earth fluoride salt waste by 90 l.%. The second technical goal is to separate useful lithium fluoride from the fluoride salt wastes with a yield over 95%. The scalability of a low-temperature wet-chemistry process in synthesizing large quantity MHPs up to 50 grams at the lab scale will also be targeted. Effective management of fluoride salt wastes are critical for the sustainable development of advanced nuclear fuel cycles and future nuclear technologies. The recycling of valuable lithium from salt waste is also significant to recover the indispensable and critical resource in large demands for advanced reactors and renewable energy applications.

Potential Impact:

By identifying and addressing challenges at the back end of the fuel cycle before the deployment of future AR technologies, ONWARDS will:


Support the growth of advanced nuclear energy with safe and sustainable domestic fuel stocks.


Play a vital role in significantly reducing GHG emissions, proactively mitigate the disposal impact of AR UNF with integrated non-proliferation safeguards, and provide transformative solutions to improve the management and disposal of radioactive waste and UNF.


Complement ARPA-E’s existing nuclear energy research portfolio, such as the MEITNER and GEMINA programs in AR R&D, further ensuring the commercial viability of innovative new ARs.


ARPA-E Program Director:
Dr. Robert Ledoux
Project Contact:
Prof. Jie Lian
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