PMMA or PVDF films blended with beta-diketonate tetrakis Eu-III or Tb-III complexes used as downshifting coatings of near-UV LEDs

Author(s)

Beltrame, Ariane C. F. ; Bispo, Airton G. G. ; Canisares, Felipe S. M. ; Fernandes, Ricardo V. ; Laureto, Edson ; Lima, Sergio A. M. ; Pires, Ana M.

• Document type: Journal article
• Source: SOFT MATTER; v. 19, n. 22, p. 10-pg., 2023-04-25.

Abstract

Luminescent Ln(III) complexes incorporated in polymeric films exhibit narrow emission bands and absorption within the near-UV/blue spectral range, and enhanced phostability, which qualify them to be explored for solid-state lighting. Herein, (C26H56N)[Eu(dbm)(4)] and Na[Tb(acac)(4)], (C26H56N+ = didodecyldimethylammonium, dbm(-) =1,3-diphenyl-1,3-propanedionate, acac(-) = acetylacetonate), were dispersed in PMMA or PVDF films to protect them from degradation, and the obtained blends were applied as downshifting coatings on near-UV emitter LEDs. Upon such excitation, both Eu-III and Tb-III complexes emit red or green light with absolute emission quantum yields of 6.4 and 99%, respectively. The complex amount within films influences the photophysical parameters due to multiphotonic deactivation, and formation of agglomerates. For the PMMA-based LED prototypes, the Ln(III) emission is well-observed while for the PVDF ones, only a poor Ln(III) emission is detected due to their opacity. Therefore, the PMMA-based systems are better candidates to be used as luminescent coatings of near-UV LEDs for solid-state lighting. (AU)

• FAPESP's process: 20/02614-0 - White-emitting silicates doped with lanthanide and transition metal ions for application in warm white-light-emitting diodes
• Grantee: Marian Rosaly Davolos
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/26103-7 - Silica particles decorated with luminescent complexes for application in sensors and cellular imaging
• Grantee: Sergio Antonio Marques de Lima
• Support Opportunities: Regular Research Grants