Photo-modulated Ionic Polymer as AdapTable Electron Transport Materials for Optically Switchable Pixel-Free Displays.

In addition to electrically driven OLED displays that rely on complicated and costly circuits for switching individual pixel illumination, developing a facile approach that structuring pixel-free light-emitting display with exceptional precision and spatial resolution via external photo-modulation holds significant importance for advancing consumer electronics. Here, we present optically switchable organic light-emitting pixel-free displays (OSPFDs) fabricated by judiciously combining an adaptive photosensitive ionic polymer as electron transport materials with external photo-modulation as the switching mode, while ensuring superior illumination performance and seamless imaging capability. By irradiating the solution-processed OSPFDs with light at specific wavelengths, efficient and reversible tuning of both electron transport and electroluminescence were achieved simultaneously. This remarkable control is achieved by altering the energetic matching within OSPFDs, which also exhibited a high level of universality and adjusTable flexibility in the three primary colors-based light-emitting displays. Moreover, we demonstrated the ease of creating and erasing desired pixel-free emitting patterns through a non-invasive photopatterning process within a single OSPFD, thereby rendering this approach promising for commercial displaying devices and highly precise pixelated illuminants. This article is protected by copyright. All rights reserved.