Ultrastrong, flexible thermogalvanic armor with a Carnot-relative efficiency over 8.

Wang, Jinpei; Song, Yuxin; Yu, Fanfei; Zeng, Yijun; Wu, Chenyang; Qin, Xuezhi; Peng, Liang; Li, Yitan et al. · Nat Commun · 2024

basic_science · Level V

Where this comes from

Abstract

Body heat, a clean and ubiquitous energy source, is promising as a renewable resource to supply wearable electronics. Emerging tough thermogalvanic device could be a sustainable platform to convert body heat energy into electricity for powering wearable electronics if its Carnot-relative efficiency (η<sub>r</sub>) reaches ~5%. However, maximizing both the η<sub>r</sub> and mechanical strength of the device are mutually exclusive. Here, we develop a rational strategy to construct a flexible thermogalvanic armor (FTGA) with a η<sub>r</sub> over 8% near room temperature, yet preserving mechanical robustness. The key to our design lies in simultaneously realizing the thermosensitive-crystallization and salting-out effect in the elaborately designed ion-transport highway to boost η<sub>r</sub> and improve mechanical strength. The FTGA achieves an ultrahigh η<sub>r</sub> of 8.53%, coupling with impressive mechanical toughness of 70.65 MJ m<sup>-3</sup> and substantial elongation (~900%) together. Our strategy holds sustainable potential for harvesting body heat and powering wearable electronics without recharging.