Electronic Correlation and Transport Properties of Nuclear Fuel Materials

TL;DR

This study uses first-principles calculations to analyze the electronic and transport properties of actinide-based nuclear fuel materials, providing insights for improving their thermophysical performance.

Contribution

It offers a systematic first-principles analysis of electron correlation and transport mechanisms in actinide fuels, which was previously not comprehensively understood.

Findings

Different transport mechanisms identified for uranium nitride and carbide.

Predictions made on how to enhance thermal conductivity of these fuels.

Insights into electron-electron and electron-phonon interactions in actinide materials.

Abstract

Actinide elements, such as uranium and plutonium, and their compounds are best known as nuclear materials. When engineering optimal fuel materials for nuclear power, important thermophysical properties to be considered are melting point and thermal conductivity. Understanding the physics underlying transport phenomena due to electrons and lattice vibrations in actinide systems is a crucial step toward the design of better fuels. Using first principle LDA+DMFT method, we conduct a systematic study on the correlated electronic structures and transport properties of select actinide carbides, nitrides, and oxides, many of which are nuclear fuel materials. We find that different mechanisms, electrons--electron and electron--phonon interactions, are responsible for the transport in the uranium nitride and carbide, the best two fuel materials due to their excellent thermophysical properties. Our findings allow us to make predictions on how to improve their thermal conductivities.