摘要
Asymmetric electrode reactivity confines viologen redox to ITO interface. • Ag/TiO₂ conduction band edge prevents electron transfer to viologen. • Voltage polarity reversal achieves electrochemically controlled bleaching. • Textile-based planar device design suits wearable electrochromic applications. This study addresses the key challenge of slow bleaching kinetics in conventional viologen-based electrochromic devices (ECDs) employing solid/gel electrolytes by proposing a novel electrode engineering strategy based on differentiated electrode reactivity. The Ag/TiO₂ fabric electrode, due to the semiconducting properties of its TiO₂ coating, exhibits insufficient reducing power to drive the reduction and coloration of dissolved viologen cations. Leveraging this principle, an asymmetric planar ECD with reaction "directionality" was constructed, consisting of an ITO electrode paired with an Ag/TiO₂ fabric electrode in a side-by-side configuration. In this design, the viologen coloration/bleaching reactions are effectively "confined" to the ITO electrode interface. Simply switching the polarity of the applied voltage (±1.0 V) enables controllable coloration (7.4 s) and active bleaching (16.5 s), which is over 98% faster than the natural diffusion-driven bleaching observed under open-circuit conditions (>900 s). Unlike conventional approaches that require complementary electroactive layers or immobilized redox species, this strategy circumvents the slow spontaneous back-reaction solely through electrode-level thermodynamic control. Furthermore, by patterning the ITO electrode, its potential for applications in flexible displays was demonstrated. This work provides a novel and effective electrode engineering strategy for developing high-performance, rapidly switchable, and designable wearable electrochromic devices. Download: Download high-res image (182KB) Download: Download full-size image
危险品化学品经营许可证（带存储）