Electrothermal and water dual-mode-responsive flexible polydiacetylene chiroptical films for multiplex laser displays

Achieving strong and dynamic tunable chiroptical responses in flexible films is highly desirable for potential applications including 3D optical displays, biosensors, and so on. Recently, controlled twisted stacking of two anisotropic layers became a popular strategy to fabricate artificial chiral nanostructures. However, in most cases, their structure and chiroptical responses are fixed, limiting their practical applications. Herein, we employed polydiacetylene (PDA)–Cs+ and PDA–Zn2+ assemblies as the individual layers within the twisted stacking structures and the hybrid films exhibited giant optical activity as well as excellent mechanical deformability. The chromatic transitions of the PDA layer under in situ water or electrothermal stimuli enable simultaneous control of two circular dichroism (CD) characteristics (magnitude and spectral position). By taking advantage of such programmable chiroptical responses, we demonstrate that PDA films have potential for full color, fast responsive, and circular polarization-based multiplex laser displays and higher-dimensional anti-counterfeiting applications. This work not only provides flexible chiral PDA films with strong and dynamic tunable chiroptical responses but is also of great fundamental value for the rational design of smart chiroptical devices.