Temperature Gradient‐Driven Multilevel and Grayscale Patterning of Tosylate‐Doped Poly(3,4‐Ethylenedioxythiophene) Films for Flexible and Functional Electronics.

Flexible conducting polymers are an integral part of emerging flexible and functional electronics such as rollables, photovoltaics, and wearables. Patterning the polymers into various surface morphologies is essential to fabricating such devices. Introduced here is an approach of realizing the pattern by polymerizing a precursor solution into the shape of the desired pattern on substrate. Selective temperature activation of the monomer precursor containing an inhibitor leads to the formation of the polymer only on the area of the desired pattern, thereby accomplishing the pattern formation. Even multilevel and graduated patterns, not readily realizable with the conventional lithography, can be formed autonomously. Flexible electrode arrays, a foldable supercapacitor, and an electrochromic device are fabricated to demonstrate the utility of the patterning approach and to showcase development of prototype devices quickly and inexpensively. [ABSTRACT FROM AUTHOR]