Repository logo

Electro-responsive surfaces with controllable wrinkling patterns for switchable light reflection–diffusion–grating devices

Accepted version

No Thumbnail Available



Change log


Lin, IT 
Choi, YS 
Wojcik, C 
Wang, T 
Kar-Narayan, Sohini  ORCID logo


Dynamic microscale surface topographies are desired in smart optics, controlling surface wettability and preventing marine biofouling. Voltage-controlled reversible responses have demonstrated potential for reliable reproducibility and stability, fast response, and for actuating thin films fixed over large solid surfaces. To obtain reversible deformation with regular geometric patterns, however, electrical methods have had to be coupled with mechanical stretching/bending and other ways to induce anisotropy. There is a great need and potential for on-demand electrical generation of programmable complex responsive surface patterns. Here we demonstrate a responsive polymer coating over an underlying pattern of counter electrodes which can be activated selectively. We present a patternable electrode printing method to achieve localized and structured wrinkling deformation without mechanical pre-force deformation. We discover that below a minimal separation distance, electrodes below the polymer act as a single electrode. We establish parameters that govern the alignment of wrinkles and quantify the regularity and direction of the new patterns between electrodes separated by larger than this distance. We analyze and quantify the regularity of the formed wrinkling patterns by four disorder metrics: box-counting fractal dimension, tortuosity, angle distribution, and branch number. We demonstrate the application of such electrode/wrinkles-on-demand patterning with a working multi-state light reflection-diffusion-grating device.



40 Engineering, 3403 Macromolecular and Materials Chemistry, 4016 Materials Engineering, 34 Chemical Sciences

Journal Title

Materials Today

Conference Name

Journal ISSN


Volume Title



Elsevier BV
European Research Council (639526)
European Research Council (280078)
Engineering and Physical Sciences Research Council (EP/L015889/1)
Cambridge Trust, China Scholarship Council, Cambridge Commonwealth, European & International Trust
Is supplemented by: