A novel approach to selection of dopant to immobilize neodymium in uranium-based metallic fuels

Abstract Formation of intermetallic compounds of lanthanide fission products within uranium-based metallic fuels with added dopant(s) has been proposed to arrest fission products within the metallic-matrix, before lanthanides chemically react with cladding materials, leading to degradation of the cladding. Unlike previous trial-and-error approach, here we present ab-initio based generic alloy-design principles to identify dopant(s) for a given lanthanide to form dopant-lanthanide intermetallic. Our approach correctly identifies previously known dopants like Pd, as well as predict novel dopants (As and Se) which can bind fission product Nd within U-matrix. Formation of our predicted NdAs intermetallic within the U-matrix has been confirmed experimentally.