Highly Photoluminescent Silica Layers Doped with Efficient Eu(III) and Tb(III) Antenna Complexes

Abstract

Eu(III) and Tb(III) antenna complexes employing different units−phenanthroline and acetophenone derivatives−for light absorption and sensitization of the lanthanide (Ln) emitting states, have been synthesized and successively anchored in silica layers by the sol−gel technique. The luminescence properties of the complexes, preliminarily studied in H2O and D2O solutions, were improved in the oxide host matrix, showing the effectiveness of the employed synthesis route for the preparation of efficient molecular-based light-emitting materials. All the prepared films were highly transparent and homogeneous and displayed a bright red (Eu3+) or green (Tb3+) luminescence notwithstanding the low luminophore content (Ln/Si = 1/400 or 1/100 molar ratios) and limited film thickness (≤140 nm). It is worth highlighting that the silica layers containing the Tb3+ complex bearing an acetophenone derivative as an antenna are characterized by photoluminescence quantum yields as high as 45%.

Layered Tb‐Doped Yttrium Carboxyphosphonate Nanocrystals as Efficient Filler for PEDOT:PSS Composite Films

“…Indeed, terbium(III) is a well‐known green emitter ( λ max =544 nm) and as such it has been widely employed in several fields . However, the population of the emissive electronic state of Tb III ( 5 D 4 state, lying at 20 500 cm −1 ) through direct light absorption is spin‐forbidden, leading to very low photoluminescence quantum efficiency.…”

“…Indeed, terbium(III) is aw ell-known green emitter (l max = 544 nm) and as such it has been widely employed in several fields. [29][30][31] However,t he population of the emissive electronic state of Tb III ( 5 D 4 state, lying at 20 500 cm À1 )t hrough direct light absorption is spin-forbidden, leadingt ov ery low photoluminescence quantume fficiency.O nt he contrary,h ighly photoluminescent Tb III complexes bearing light absorbinga ntennas able to sensitize the lanthanide emission have been reported. [32,33] In 2mw,t he glyphosate acts as coordinating unit, UVlight absorbing and sensitizing antenna, as its excitation leads to ad etectable Tb III centered emission.H owever,t he Tb III -centered photoluminescence can be strongly affected and quenched also in antenna-lanthanide complexes, depending upon severalf actors.…”

Highly‐Luminescent DTTA‐Appended Water‐Soluble Lanthanide Complexes of 4‐(Het)aryl‐2,2′‐bipyridines: Synthesis and Photophysical Properties

“…In continuation of our researches on 2,2′‐bipyridine ligands for lanthanide cations in this manuscript we wish to report our studies on the 2,2′‐bipyridine‐based ligands substituted with DTTA residue attached through a methylene unit at the alpha position of the edge pyridine core. In a literature, the earlier examples of such complexes are very limited and, thus, more detailed studies are highly desirable.…”

Synthesis and luminescence properties of cinnamide based nanohybrid materials containing Eu (II) ions

“…Most researches have been focused on the photoluminescence features of lanthanide-based hybrid matrices [7][8][9][10][11], seeking essentially to take advantage of the high chromaticity and long lived excited-states characteristic of the metal ions. Rare-earth ions incorporated in metal oxides, nitrates, or halides are usually stabilized in trivalent states.…”