2D Chalcogenide Thermoelectric Materials for Enhanced Solar Collection

Even for high efficiency photovoltaics (PVs), a considerable amount of energy is lost as waste heat. One of the largest areas of loss is incoming photons with energy below the photovoltaic bandgap. These photons, not contributing to the performance, only heat up the PV, which has been shown to decrease efficiency. A method of capturing this waste heat is to place a thermoelectric behind the photovoltaic. With one side in contact with the back of the solar cell, and the other exposed to the open environment, this can create a sufficient temperature gradient to produce a voltage, and ultimately power. In this work, we present flexible 2D chalcogenide thermoelectric films adhered to the back of traditional planar photovoltaics as a method of heat management. With the benefit of being both lightweight and requiring minimal post processing, the photovoltaic-thermoelectric devices are suitable for both terrestrial and extraterrestrial environments. Tested films include bismuth telluride and antimony telluride, with increasing amounts of silver and copper doping, to improve thermoelectric performance.