6.They work because certain materials, such as bismuth telluride, generate an electrical potential difference within themselves if one part is hotter than another.
7.The third objective, efficient design, involved sandwiching the nanostructured bismuth telluride between two copper plates and then enclosing the upper plate (the one coated with the light-absorbing oxides) and the bismuth telluride in a vacuum.
8.“To absorb a useful amount of sunlight with silicon we would need to use around 200 micrometers of material. " Major said. " For absorbers such as cadmium telluride, we need to use only 1 percent of the same material.”