Use of Different Metal Oxide Coatings in Stainless Steel Based ECDs for Smart Textiles

Abstract

Electrochromism is the ability of a material to selectively change its coloration under the influence of an external electric current/potential and maintain it even after the power source has been disconnected. Devices that use such a mechanism are known as electrochromic devices (ECDs). Over the years, significant effort has been invested into the development of flexible ECDs. Such electrochromic tapes or fibers can be used as smart textiles. Recently, we utilized a novel geometrical approach in assembling electrochromic tapes which does not require the use of optically transparent electrodes. The so-called inverted sandwich ECD configuration can employ various color-changing mechanisms, e.g., intercalation, redox reactions of electrolytes or reactions on electrode surfaces. One of the most frequently used electrochromic metal oxides is WO3. However, other metal oxides with different coloration responses also exist. In this paper, we explore the use of V2O5 and TiO2 in metal-tape-based ECDs in the inverted sandwich configuration and compare their performance with WO3-based devices. Morphological features of metal oxide thin layers were investigated with scanning electron microscopy (SEM), and the performance of the tapes was investigated electrochemically and spectroscopically. We demonstrate that well-established preparation techniques (e.g., sol–gel synthesis) along with coating approaches (e.g., dipping) are adequate to prepare optically nontransparent fiber electrodes. Depending on the metal oxide, flexible electrochromic fiber devices exhibiting different coloration patterns can be assembled. Devices with TiO2 showed little coloration response, while much better performance was achieved in the case of V2O5 and WO3 ECDs.

Transparency- and Repellency-Enhanced Acrylic-Based Binder for Stimuli-Responsive Road Paint Safety Improvement Technology

“…A continuously increasing amount of research and development of smart polymers and stimuli-responsive polymers, such as the manufacturing of biomedical application materials using heat sensitive materials [1][2][3][4][5], external stimuli-responsive materials and application technology [6][7][8], smart polymer materials with nanostructured surfaces for biomolecular recognition and bonding [9][10][11], and smart polymer materials sensitive to temperature and light, is being carried out. As interest in smart materials is rapidly increasing in the electronics and automobile industries, automobiles, smart displays, energy harvesting, sensor devices, and smart coating materials are also representative research fields [12,13]. Road marking technology should have the characteristics of phosphorescence, fluorescence, and retroreflection by photostimulation (sunlight, streetlamp lighting, automobile headlight, etc.)…”