Optimizing thin-film pyroelectrics: https://phys.
Post# of 22456
https://phys.org/news/2018-04-thin-electronics-energy.html
*aka; thermoelectric....this was one of the many uses for QD's that many had envisioned years ago, but like so many others, this faded into distant memory for reasons unknown. This article sheds some light on the difficulties, processes & hurdles still to be overcome before this tech becomes practical.