Photoactive Europium Hybrids of β‐Diketone‐Modified Polysilsesquioxane Bridge Linking Si–O–B(Ti)–O Xerogels

Abstract

Polysilsesquioxane bridges are obtained through the single modification of 3‐(triethoxysilyl)propyl isocyanate (TEPIC) by two β‐diketone ligands [thenoyltrifluoroacetylacetone (TTA) and trifluoroacetylacetone (TA)], which behave as linkages between the europium ion and composite host Si–O–M (M = B or Ti) xerogels by controlling the hydrolysis rate of the alkoxy compounds (tetraethyl orthosilicate, titanium butoxide and tributyl borate). Subsequently, luminescent europium hybrid xerogels are assembled and characterized by NMR, Fourier transform infrared (FTIR), ultraviolet absorption and ultraviolet/visible diffuse reflection spectroscopy, X‐ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and photoluminescence spectroscopy through which the decay times (τ) and quantum efficiency (η) can be determined. These results reveal that the lanthanide complexes have been covalently immobilized into the composite inorganic xerogels and the obtained hybrids have the excellent ability of light absorption and emission. The hybrids with composite Si–O–B xerogels possess the matched photoluminescent properties (red emission intensity, lifetimes, and quantum efficiency) as the pure silica oxygen network, both of which show a superior luminescence performance than the hybrids with composite Si–O–Ti xerogels. Besides, the single modification of TTA is favorable for the luminescence of the hybrid xerogels.

Photoluminescent Properties of Novel Rare Earth Organic–Inorganic Nanocomposite with TiO2 Modified Silica via Double Crosslinking Units

“…Only one kind of hybrid material with single silica host Phen-RE-MBA-Si belong to amorphous materials because of the nature of silica. Here, the organically modified silica is noncrystalline solid materials, which have been studied extensively (9)(10)(11)(12). The nature of silica cannot be change.…”

“…But, the inorganicorganic hybrid materials covalently grafted with rare earth complexes are mainly developed for silicate systems. Recently, some works have been extended to other inorganic hosts such as titania, borate and alumina systems (7)(8)(9)(10)(11)(12). Among titania can be introduced to hybrid system through the organic carboxylic derivative as linkage (8,12).…”

Photophysical Properties of Ternary RE3+ (RE = Eu, Tb, Sm) Hybrids with β-Diketone Functionalized Linkages and 4-(4-nitrostyryl)pyridine Though Coordination Bonding

“…Following the literature procedure [19][20][21][22][23][24][25], the bridge molecules TTA-Si and the TAA-Si are acquired. Firstly, TTA (2 mmol, 0.444 g) is dissolved in 20 mL of dehydrate THF and NaH is added into the solution with stirring, 2 h later the TEPIC (4 mmol, 0.990 g) is then put into the refluxing solution by drops.…”

“…We take the bridge molecule as the organic ligand and the Nspy as the second ligand to construct the better luminescent hybrid systems. In these hybrid systems, the bridge molecule and Nspy can coordinate to the RE 3+ by the carbonyl groups and nitrogen atom respectively, the Si-O network is formed after the cohydrolysis and copolycondensation processes between the bridge molecule and the tetraethoxysilane (TEOS) [19][20][21][22][23][24]. The characteristics of the resulting materials are analyzed and compared in details.…”

Luminescent Eu3+/Tb3+ immobilized in 5-amino-iso-phthalate functionalized hybrid gels through di-urea bridge

“…More recently, some works have been reported on the sol-gel derived hybrid materials from the titanium alkoxyl compounds, while it is not satisfied with the luminescent properties comparing to the corresponding silica-based hybrids [7,8]. We have also tried to prepare the hybrids with composite host network which is derived from the different alkoxyl compounds by controlling their co-hydroysis and copolycondensation processes [9,10]. The introduction boron into organic-inorganic hybrid materials will probably improve these materials and thus generate new materials with more advanced properties.…”