Aggregation‐Induced Emission and Single‐Molecule Magnet Behavior of TPE‐Based Ln(III) Complexes

Abstract

Multifunctional lanthanide complexes have been studied extensively owing to their promising applications in information storage, luminescence sensors and magnetooptical devices, etc. Here, we report the facile synthesis of two discrete highly thermally stable lanthanide compounds, Ln(hfac) 3 (TPE-tz) (Ln = Eu, Dy), by the reaction of the AIEactive organic ligand with Ln(III) β-diketonate precursor. Due to different energy gaps between the triplet state of the ligand and the accepted level of Ln(III) ions, Eu(hfac) 3 (TPE-tz) exhibited remarkably enhanced luminescence intensity upon aggregation, i. e., a typical AIE behavior, while Dy(hfac) 3 (TPEtz) displayed weak characteristic emission bands of Dy(III) ions. In addition, Dy(hfac) 3 (TPE-tz) showed field-induced SMM behavior. This work shows that careful choice of auxiliary ligands paves the way for the construction of multifunctional lanthanide smart materials.

Progresses and Perspectives of Near-Infrared Emission Materials with “Heavy Metal-Free” Organic Compounds for Electroluminescence

“…The choice of different, electron-rich and electron-poor units along the π-conjugated, organic backbone of the molecule could control the material functionality for organic electronic applications through the push-pull effect. Futhermore, the substitution pattern of carbazole modified the molecule properties [ 115 , 116 , 117 ] because carbazole has fine optical and electronic properties and high chemical stability. OLEDs based on M23 presented efficient emission in red and infrared spectral ranges, with an EQE of 3.13%.…”

The effect of magnetic coupling along the magnetic axis on slow magnetic relaxation in DyIII complexes with D5h configuration based on an aggregation-induced-emission-active ligand

“…[34][35][36][37][38] At present, research on AIE is mainly focused on organic compounds, where there are only a few examples of complexes exhibiting AIE effects, especially lanthanide complexes. [39][40][41] AIE materials usually reveal stimuli-responsive changes as luminous color or intensity, which correspondingly modulate the crystal symmetry or molecular packing mode, thereby influencing the magnetic properties. 42 Inspired by these charming properties of SMMs and AIE effects, we chose TPE-based pyridine-carbohydrazone Schiff base ligands (H 2 TPE-pc, Scheme 1) as building blocks to construct dinuclear Dy III complexes with the aid of phosphine oxides.…”