TRANSPORT INVOLVING CONDUCTING FIBERS IN A NON-CONDUCTING MATRIX

Thermal and electrical transport through a low-conductivity matrix containing high-conductivity fibers is important to sev-eral applications including flexible thin-film transistors, PEM fuel cells, and direct energy-conversion devices. Nanofibers can limit thermal transport through phonon confinement and boundary scattering while maintaining high electrical con-ductivity. The substrate will not contribute to electrical per-formance but may participate in thermal transport. The net result is a material whose Lorenz number can be tuned by loading the matrix with fibers. The purpose of the present work is to investigate the effectiveness of several transport models in the context of two-dimensional fiber composites and to compare the thermal and electrical transport through a given material as a function of the conductivity ratio an