Professor Di Yun focuses on developing advanced nuclear fuel materials. On the theoretical front, he developed a novel high burn-up metallic fuel concept for fast neutron reactors; he also investigated in fundamental aspects of nuclear fuel performance modeling and applied multi-scale simulation methods to address fuel performance issues. On the experimental front, he has investigated in the underlying mechanisms of oxidation kinetic transition of Zircaloys and is also developing nitride coatings for advanced nuclear fuel systems for light water reactors; he is currently pushing for development of such materials into real engineering application scenarios.