LUMINESCENCE FEATURES OF COMPOSITE FILMS BASED ON ANISOMETRIC COMPLEXES OF EUROPIUM(III) AND TERBIUM(III) DOPED INTO A POLYLACTIDE MATRIX
Rubrics: 1. CHEMISTRY
Authors:
1.
Kazan National Research Technological University
2.
KNITU
3.
KNITU
Type:
Article
Pages:
from 22
to 27
Status:
Published
Received:
10.03.2026
Accepted:
10.04.2026
Published:
05.05.2026
Language:
Russian
Keywords:
LANTHANIDE COMPOUNDS, β-DIKETONATES, POLYLACTIDE, COMPOSITE FILMS, LIGHT CONVERTERS
Funding:
Issledovanie vypolneno pri v ramkah Gosudarstvennogo zadaniya № 075-00021-26-00 ot 12.01.2026 (FZSG-2026-0003).
Abstract:
New composite films based on a polylactide (PLA) matrix and Eu(III) and Tb(III) tris(β-diketonate) complexes with 1,10-phenanthroline were synthesized, and their optical properties were studied. To obtain films with varying phosphor concentrations, solutions of mixed Tb(III), Eu(III), and PLA complexes in toluene were deposited onto a quartz substrate using spin-coating. Composites based on lanthanide complexes and polymers exhibit improved photoluminescence properties, thermal stability, and flexibility due to the uniform distribution of the complex within the polymer macromolecular chains. In this regard, polylactide is an ideal matrix for rare earth ions due to its optical properties, processability, comparatively low cost, and suitability for 3D printing. Therefore, the production and study of new composite materials based on lanthanide(III) coordination compounds and polylactide polymer is a highly interesting and relevant task. It was established that high ligand coordination increases the photostability of the complexes, while long hydrocarbon substituents in the structure prevented their crystallization and facilitated good miscibility with the polymer, which allowed for an increase in the phosphor content in the polymer matrix and the achievement of maximum emission at higher concentrations of the emitting ion. In the emission spectra of the films, with increasing phosphor concentration, the luminescence intensity increases and reaches a maximum for the Tb(III) complex at 12.5 wt.% and for the Eu(III) complex at 20 wt.%, respectively. This was due to concentration quenching of luminescence. Moreover, for most similar systems based on lanthanide compounds known from the literature, the effective phosphor content typically does not exceed 5-10%. The films were virtually transparent in the visible and IR regions (transmittance greater than 90%) and exhibited absorption in the ultraviolet region. Thus, it has been shown that the structural features of anisometric compounds allow the production of composite materials with significantly less luminescence self-quenching than their analogs. This opens up broader possibilities for the application of Ln(III) coordination compounds as polyfunctional film materials for optics and optoelectronics.
New composite films based on a polylactide (PLA) matrix and Eu(III) and Tb(III) tris(β-diketonate) complexes with 1,10-phenanthroline were synthesized, and their optical properties were studied. To obtain films with varying phosphor concentrations, solutions of mixed Tb(III), Eu(III), and PLA complexes in toluene were deposited onto a quartz substrate using spin-coating. Composites based on lanthanide complexes and polymers exhibit improved photoluminescence properties, thermal stability, and flexibility due to the uniform distribution of the complex within the polymer macromolecular chains. In this regard, polylactide is an ideal matrix for rare earth ions due to its optical properties, processability, comparatively low cost, and suitability for 3D printing. Therefore, the production and study of new composite materials based on lanthanide(III) coordination compounds and polylactide polymer is a highly interesting and relevant task. It was established that high ligand coordination increases the photostability of the complexes, while long hydrocarbon substituents in the structure prevented their crystallization and facilitated good miscibility with the polymer, which allowed for an increase in the phosphor content in the polymer matrix and the achievement of maximum emission at higher concentrations of the emitting ion. In the emission spectra of the films, with increasing phosphor concentration, the luminescence intensity increases and reaches a maximum for the Tb(III) complex at 12.5 wt.% and for the Eu(III) complex at 20 wt.%, respectively. This was due to concentration quenching of luminescence. Moreover, for most similar systems based on lanthanide compounds known from the literature, the effective phosphor content typically does not exceed 5-10%. The films were virtually transparent in the visible and IR regions (transmittance greater than 90%) and exhibited absorption in the ultraviolet region. Thus, it has been shown that the structural features of anisometric compounds allow the production of composite materials with significantly less luminescence self-quenching than their analogs. This opens up broader possibilities for the application of Ln(III) coordination compounds as polyfunctional film materials for optics and optoelectronics.
Keywords:
LANTHANIDE COMPOUNDS, β-DIKETONATES, POLYLACTIDE, COMPOSITE FILMS, LIGHT CONVERTERS
LANTHANIDE COMPOUNDS, β-DIKETONATES, POLYLACTIDE, COMPOSITE FILMS, LIGHT CONVERTERS
