Breaking trade-off problem that limits thermoelectric conversion efficiency of waste heat

https://www.titech.ac.jp/english/news/2021/062112

"electric power is evaluated by power factor (PF), which is the product of thermopower S squared and electronic conductivity (s)... the s increases with increasing impurity concentration but the S decreases. This trade-off limits the PF... a way to break this trade-off... increase in both S and s resulted in a hundred-fold increase in PF... by greatly improving the thermoelectric performance of oxides beyond the trade-off relationship, thermoelectric conversion is expected to become widespread as a general energy source"