Diffusion controlled degradation analysis of high temperature (Bi,Sb)2(Te,Se)3 semiconductor thermoelectric power modules

Closed-packed array (Bi,Sb)2(Te,Se)3 compound semiconductor thermoelectric power modules have been used extensively in terrestrial thermoelectric generators for converting thermal energy directly into electricity. In this paper a diffusion controlled degradation model based on a new modified Whipple-type grain boundary diffusion model has been developed. This model considers the effect of temperature gradient on a high diffusivity path and has been developed for studying the degradation mechanism of (Bi,Sb)2(Te,Se)3 compound semiconductor power thermoelectric modules caused by the formation of dark bands.