High-Temperature Transport Properties of Palladium

Abstract

The thermal conductivity, electrical resistivity, and absolute thermoelectric power of pure palladium have been determined from 90 to 1300 K in two experimental systems of proven reliability. These properties are compared with the sparse available literature data, and show large deviations from them, particularly for the thermal conductivity at high temperatures. The results are also analyzed in terms of a simple two-band model, where one band contains the carriers, and the other acts as a trap into which phonons scatter the carriers. When the recent density of states values of Mueller et al. are used, the model predicts correctly the temperature variation of the electrical resistivity, and reasonably well its observed magnitude and the observed Wiedemann–Franz ratio. However, the model fails badly in respect to the absolute thermoelectric power, predicting values twice as large as the observed ones. Modifications to the model are suggested which may improve the fit between the predicted and observed values.