Multicolor electrochromic fabric with a simple structure of PEDOT:PSS/DMSO

Smart textiles with highly controllable and tunable color changes have attracted considerable attention because of their promising practical application functionality, such as military clothes, sensors, decorations, and protective purposes like information encryption and alert, including thermochromism, photochromism, electrochromism, etc. Among them, the color variation of stimulus-responsive fabric triggered by electricity is more conveniently and effectively controlled than the color change that relies on stimuli like temperature and ultraviolet radiation. Poly(3,4-ethylenedioxythiophene):poly(styrenesulfo-nate) (PEDOT:PSS) are one kind of the most promising electrochromic materials. Currently, electrochromic fabrics (ECFs) based on PEDOT:PSS is still hindered by relatively poor conductive efficiency and complex structure. Here, we developed a multicolor ECFs with a simplified structure using polyester (PET) fabric, PEDOT:PSS/dimethy sulfoxide (DMSO), ionic liquids as an electrochromic container, a conductive color-changing layer and ion transfer medium, respectively. Therein, PEDOT:PSS enhanced conductivity by changing the conformation with DMSO. The conductive solution PEDOT:PSS/DMSO was coated on the flexible PET substrates and then treated with ionic liquids as a conductive layer and redox reactions functional layer to realize the color-changing. These ECFs exhibited impressive electrochromic behavior with color-changing between light blue and dark blue. Moreover, the device was endowed with hydrophobicity and self-cleaning by spraying commercially available hydrophobic agents. To overcome the monochromatic color-changing capacity of traditional ECFs, subtractive principle was introduced to design multicolor electrochromic fabric. Multicolor electrochromic along with excellent flexibility, stability, and lightweight features, are practical for camouflage applications, such as the reversible yellow-green conversion that can adapt to land and grass fighting scenes. We believe the simple-structured multicolor electrochromic fabric would be promising for flexible display in any textile-based markets, such as adaptive camouflage.