Electrically Driven PANI-Based Multilayer Nanocomposite Coatings for Dynamic Color Modulation

Reconfigurable precision regulation of structural color devices is a critical step toward versatile advanced functionality and broadening application scenarios. In this work, we demonstrate the precise manipulation of red, green, and blue, three primary colors generated by the five-layer nanocomposite coatings composed of polyaniline/indium tin oxide/titanium/titanium dioxide/titanium (PANI/ITO/Ti/TiO2/Ti). The modulation of dynamic structural colors of the proposed multilayer coatings originates from a cooperative interaction between the top PANI conductive polymer and the bottom traditional four-layer structural color consisting of ITO/Ti/TiO2/Ti. Specifically, the three primitive colors are first achieved by three different combinations of both TiO2 and ITO thicknesses, and then each color is modulated precisely by an intrinsic color change of the top PANI conductive layer at various voltages. As a result, the nanocomposite coatings demonstrate millisecond response time, excellent durability over 100 cycles, driving voltages below 1 V, and a wide temperature tolerance range from 5 to 60 °C. Additionally, centimeter-scale R, G, and B letter-shaped samples are fabricated using a mask plate coating technique, showcasing color modulation in patterned samples. Our work offers a straightforward strategy to realize the dynamic manipulation of the three primary colors within a certain range, which lays a solid foundation for the development of dynamic display technologies, such as dynamic paintings and e-books.