Two-component polymers embedded with tungsten oxide nanoparticles toward broadband and nonvolatile photomemory

Abstract

Photochromic materials exhibit adjustability of their physical parameters to external light stimulus, regarding as an important carrier of optical memory. However, the reversible photochemical reaction in such a medium inhibits the permanent preservation of data. Herein, we propose to embed photochromic tungsten oxide nanoparticles into two-component polymers of polyvinyl alcohol/polyacrylic acid (PVA/PAA). Thermal relaxation of the coloring state is effectively inhibited in the proton-rich polymer matrix, so as to enhance the life, rate and efficiency of photomemory. Moreover, photochromic response boundary extends from near-ultraviolet to green region, realizing colorful hologram reconstruction. This work provides an important strategy for developing broadband, persistent and flexible photonic devices.