Harvesting Energy from Human Body Heat

This article describes a device for harvesting infrared energy from human body thermal radiation into electrical energy. The device takes advantage of quantum dots made of lead sulfide and couples multiple electronic excitations between mid-gap states to span the optical bandgap.

Applied Energy 230 (2018) 761–768
"Lead sulfide colloidal quantum dot photovoltaic cell for energy harvesting from human body thermal radiation"

Taher Ghomiana, Orhan Kizilkaya, Jin-Woo Choi

In this paper, we present the development of a solution-processed photovoltaic structure designed to convert human body thermal radiation into electricity. An active layer composed of a layer of isopropylamine-capped lead sulfide (PbS) quantum dots (QDs) covered with a layer of lithium chloride (LiCl) on top is sandwiched between a substrate and an aluminum contact. Experimental measurements reveal that the device was sensitive to infrared radiation with energies lower than the optical bandgap energy of the incorporated nanocrystals (Eg=1.26 eV), allowing one to harvest thermal radiation from a human body. We used a conceptually different approach to harvest this radiation by intentionally introducing mid-gap states to the lead sulfide quantum dots through passivation with isopropylamine and likely enabling a multi-step photon absorption mechanism.