Highly Responsive Photochromic Ceramics for High‐Contrast Rewritable Information Displays

Abstract

Inspired by their excellent thermal stability and strong fatigue resistance, inorganic photochromic materials have been highlighted as promising candidates in various photonic applications ranging from photoswitches, anti-counterfeiting, and encryption to information storage. However, the lack of suitable inorganic materials with both fast photoresponse and strong coloration contrast heavily restricts their applications. Herein, a new strategy is proposed to achieve high photochromic performance via constructing deep-lying traps in ferroelectric ceramics. The obtained K 0.5 Na 0.5 NbO 3 -Eu (KNN-Eu) ceramic exhibits a reversible yellow-gray color change with high fatigue resistance upon alternating illumination (420 nm) and thermal stimulus (450°C). A fast response time of around 1 s and a large reflectivity difference of 39.2% between the colored and bleached states are simultaneously achieved in KNN-Eu ceramic, which is by far the best performance ever reported in inorganic photochromic materials. Benefiting from these excellent properties, KNN-Eu is the first ferroelectric photochromic ceramic to support an instant and hand-(re)writable information display. The enhanced photochromic performance is expected to facilitate the application of photochromic materials in numerous optical devices and provides a significant guidance to design other inorganic photochromic materials.

Halogen-doped phosphorescent carbon dots for grayscale patterning

“…The developing trend in both optics and materials science therefore has introduced requirements for photoresponsive materials with programmable dynamic performance, namely, the ability to record, reproduce, and erase optical information by phototriggering. To meet this need, materials with photoprogrammable absorption 1 , 4 – 7 , fluorescence 6 – 10 , and even phosphorescence 11 – 14 have recently emerged, demonstrating great potential in display, imaging, and optical encryption.…”

Immobilization of lanthanide doped aluminate phosphor onto recycled polyester toward the development of long‐persistent photoluminescence smart window

“…An excitation source is required to activate fluorescence of a certain material, and the light emission of this material is immediately restored when this supply is removed. [ 19 ] This light emission of the excited material can continue for a few seconds to indicate phosphorescence or continue emission for hours to indicate long‐persistent phosphorescence afterglow. A light‐induced color shift that occurs to a certain material under an excitation source and after that returns to its original color when the excitation supply is removed is known as photochromism.…”

Large reversible upconversion luminescence modification and 3D optical information storage in femtosecond laser irradiation-subjected photochromic glass

“…Photochromic materials with absorption and photoluminescence modulation were recently developed as novel optical data storage media [9][10][11]. As established guiding rules for the optical storage application of photochromic materials, a fast photoresponse, large storage capacity, nondestructive reading, and high coloration and luminescence contrast are required [12,13]. Inorganic photochromic materials have garnered extensive attention as optical information storage media owing to their high strength or mechanical resistance, good thermal and chemical stabilities, and low environmental toxicity [14][15][16].…”