Multistimuli-responsive circularly polarized luminescent material of achiral Eu-containing polyoxometalates and cellulose nanocrystals

Abstract

The stimuli-responsive circularly polarized luminescence (CPL) material was made using photonic cellulose nanocrystals (CNC) and achiral luminescent Eu-containing polyoxometalates Na9EuW10O36·32H2O (EuW10). The CPL of EuW10 with high dissymmetric factor glum ~ −0.37 was achieved based on the selective reflection property of CNC photonic films. With the increase of polyethylene glycol (PEG) content, the photonic bandgaps (PBG) of CNC/PEG/EuW12 composite films were redshifted, successfully achieving the chirality of EuW10 in various emission bands (5D0→7Fn, n = 1, 2, 3, 4). The CPL materials also showed excellent humidity responsiveness. The glum of the emission band was closely correlated to the PBG of composite films.

Keywords

• circularly polarized luminescence
• cellulose nanocrystals
• polyoxometalates
• stimuli-responsive