Self-healable luminescent materials via a supramolecular self-assembly design

Abstract Supramolecular self-assembly induced by lanthanide ions (Ln3+) provides a powerful route to construct advanced functional materials, owing to the highly predictable nature of the Ln-ligand coordination and unique physical property of Ln3+. Herein, we synthesized functional luminescent materials by incorporation of fluorescent centers into polydimethylsiloxane polymers via supramolecular self-assembly design, where the coordination connection and hydrogen bond endow the materials with fast self-healability and good mechanical performance at room temperature: (i) the self-healing material PIB-Ln prepared by introducing Ln3+ into the precursor exhibits response to stimuli of acid-base vapors on account of the inhibition or promotion of “antenna effect” upon stimulation (the as-prepared precursor is named as PIB). This reversibly responsive fluorochromic material displays promising application in smart sensors; (ii) the highly fluorescent material PIB-Eu-TTA was prepared by bonding Tris(2-thenoyltrifluoroacetonato) (TTA) europium(III) dihydrate complexes (Eu(TTA)3·2H2O) to the bipyridine groups on the precursor. Compared to PIB-Ln, PIB-Eu-TTA shows faster self-healing property and more high stretchable feature on account of the smaller steric hindrance of PIB-Ln-TTA and better fluorescent behavior because of the coordinated water molecules being expelled and energy transfer effectively from tris(2-thenoyltrifluoroacetonato) to Eu3+. On the basis of the superior performance, PIB-Eu-TTA demonstrates an exemplary application in a flexible and self-healable conductor and light-emitting diode (LED), thereby providing new insight into the future development of e-skin and smart optical devices.