Electrospun Photochromic Hybrid Membranes for Flexible Rewritable Media

Ink-free rewritable media has attracted great attention as a potential alternative to current paper prints, owing to its benefits to reducing paper production and consumption for environmental protection. It is desirable to develop rewritable media based on cheap, robust, and fast-response photochromic systems. Herein, we report the design and fabrication of flexible and photorewritable PVP/a-WO3 hybrid membranes through electrospinning, on which images with high resolution can be photoprinted and heat-erased for over 40 cycles. The well conjugated organic–inorganic hybrid structure endows a fast “electron–proton double injection” from PVP to a-WO3 in the coloration process and greatly improves the photochromic responses. The coloration times can be as short as tens of seconds and the erasure times can be as long as 10 days in ambient conditions. As-formed photochromic membranes are low-cost, environmental benign and easy for large-scale production, indicate their great potential as flexible rewritable media for practical usage.无墨可重写介质作为现有纸质印刷品的潜在替代方案，凭借其在减少纸张生产与消耗、助力环境保护方面的优势，已受到广泛关注。开发基于低成本、稳健可靠且响应快速的光致变色体系的可重写介质，极具研究价值与应用前景。在此，我们报道了通过静电纺丝法制备柔性可光重写的聚乙烯吡咯烷酮/无定形三氧化钨（Polyvinylpyrrolidone, PVP/amorphous tungsten trioxide, a-WO3）杂化膜；该膜可实现高分辨率图像的光印刷与热擦除，且可重复循环40次以上。该结构优异的有机-无机杂化体系，在着色过程中可实现从PVP到a-WO3的快速“电子-质子双注入”，显著提升了光致变色响应性能。在室温环境下，该膜的着色时间可短至数十秒，而图像擦除时间最长可达10天。所制备的光致变色膜具备低成本、环境友好且易于规模化生产的优势，展现出作为柔性可重写介质用于实际应用的巨大潜力。