Smart emissive materials able to react reversibly to an external stimulus are of considerable interest in many fields such as optoelectronics, recording and data storage, and display ... A multidisciplinary consortium of chemists from the Institute of Chemical Sciences in Rennes (ISCR) has developed a printable hybrid material able to withstand numerous write-erase cycles. This material, which was the subject of an European patent application in collaboration with the SATT Ouest Valorisation (Eur.Pat Appl., N: 19395523.3), is obtained by homogenous integration of an organic blue green 3-oxindole emitter and a red NIR phosphorescent octahedral metal cluster. Studies carried out on the Caphter platform (UMS ScanMat) have shown that irradiating these hybrid films with a basic UV lamp modifies their emission colour from white to red thanks to energy transfers modulated by oxygen. This phenomenon allows, for example, to encrypt informations temporarily directly on the film. By adjusting some parameters, the lifetime of the encrypted data may vary from a few minutes to several days. Once the message is self-erased, the media is reusable. A mission not impossible for Jim Phelps and Ethan Hunt, and a good point for sustainable development.
Doped films under white light (top) and UV light (bottom) containing from left to right: the blue emiisive 3 oxindole, the red phosphorescent metal cluster and both emitters.
Soumaya Khlifi, Nicolas Fournier Le Ray, Serge Paofai, Maria Amela-Cortes, Huriye Akdas-Kiliç, Grégory Taupier, Sylvie Derien, Stéphane Cordier, Mathieu Achard, Yann Molard*
Materials Today, accepted
Univ Rennes, CNRS, ISCR - UMR 6226, ScanMAT – UMS 2001, F-35000 Rennes, France