Thermal Conductivity Across Metal/Metal Oxide Interfaces

The National Renewable Energy Laboratory has proposed a new method to reduce heat waste of catalytic cracking, which involves inductively heating the catalyst through a layered metal/metal oxide device. We demonstrate a computational method for predicting thermal conductivity across metal/metal oxide systems using molecular dynamics (MD) with a two-temperature model (TTM). The TTM allows thermal conductivity to be modeled with a combination of lattice and electronic contributions by governing the exchange of energy between the lattice and an electronic subsystem.

Our method predicts thermal conductivities of bulk iron and iron oxide to the same order of magnitude as experiment. The addition of the TTM improves the prediction of thermal conductivity of iron compared to MD alone, indicating significant electronic contributions in the thermal conductivity of iron. The TTM is not applicable to iron oxide due to a deficiency of conduction electrons. Our results indicate a large temperature drop across the metal/metal oxide interface. Our approach is transferable to other metal/insulator systems.