Strain-enhanced electrical performance in stretchable semiconducting polymers

Intrinsically stretchable semiconducting polymers are promising candidates for developing wearable electronics, but remain underdeveloped because the correlation between the microstructural evolution during stretching and the resultant charge transport is not clearly understood. In this study, we clarify the impact of molecular orientation on the dynamic performance of stretched semiconducting polymers, controlling molecular orientations via solvent-dependent spin-coating. We found that strain-enhanced electrical performance is feasible by quelling disorders within the face-on-packed aggregates. Strain facilitates 3D ordering in face-on-packed films, but increase the π-π orientation disorders and lamellar dislocation in the edge-on analogue, which contribute inversely to the charge transport. Consequently, the face-on samples maintain strain-resistant energetic disorder and a 1.5× increase in on-current, achieving a 10-times-higher retention than the edge-on analogue upon 100% strain. Furthermore, we developed a reliable way for measuring the photoelectrical stretchability of semiconducting polymer. This study contributes to developing high-performance stretchable semiconducting polymers.