Luminescent Hybrid Research Articles

Ultrastable luminescent hybrid microporous polymers based on polyhedral oligomeric silsesquioxane for CO2 uptake and metal ion sensing

In this study we prepared four different fluorescent hybrid microporous polymers (HPPs) derived from cubic octavinylsilsesquioxane (OVS) through Heck coupling with brominated anthracene (An-Br2), triphenyltriazine (TPT-Br3), bicarbazole (Car-Br4) and tetraphenylethene (TPE-Br4). The chemical structures of these HPPs were confirmed using Fourier transform infrared spectroscopy and solid-state NMR spectroscopy. Thermogravimetric analysis and N2 adsorption/desorption measurements revealed that each of these HPPs had outstanding thermal stability, a high surface area, and inherent porosity. The CO2 uptakes of TPT-HPP and Car-HPP at 273 and 298 K were higher than those of An-HPP and TPE-HPP. Furthermore, the luminescence of these HPPs could be quenched completely upon the addition of Fe2+, and Fe3+ metal cations. Thus, these HPP materials appear to be good candidates for CO2 adsorption and metal ion sensing.

Fabrication of composite Fe3O4 nanoparticles coupled by thermo-responsive and fluorescent Eu complex on surface

Stimuli-responsive luminescent hybrid nanoparticles consisting of a magnetite Fe3O4 core and a hydrophilic outer shell were synthesized. The shell was a thermo-responsive Eu(III) complex shell, which was synthesized as follows: first, 3-Methacryloxypropyl-trimethoxysilane (MEMO)-co-poly(N-isopropylacrylamide) (NIPAM) (MEMO-co-PNIPAM) copolymer was prepared by free radical polymerization. Subsequently, the copolymer chelated with Europium(III) ions to form a luminescent polymeric layer. Finally, the polymeric shell was grafted onto the Fe3O4 nanoparticles surface through chemical action. The sizes of fabricated nanoparticles with core–shell structure were controlled at about 30-45 nm. The as-synthesized nanocomposite particles had excellent fluorescence performance and thermo-responsive behavior, which possessed high color purity and produced red-emission at 613 nm. The lower critical solution temperature (LCST) of thermo-sensitive magnetic nanoparticles was at around 37–38 °C. Cell viability assays suggested that these nanoparticles showed excellent biocompatibility and fluorescence-intensity in vitro.

Eu-phen Bonded Titanium Oxo-Clusters, Precursors for a Facile Preparation of High Luminescent Materials and Films.

Incorporation of Eu complexes into various organic or inorganic matrixes is one of the acceptable strategies to obtain displaying materials having practical applications. In this work, we report a convenient approach to preparing high luminescent organic-inorganic hybrid materials and films from the europium-titanium oxo-clusters (EuTOCs) having photoactive antenna ligands. Three Eu2Ti4 oxo-clusters were synthesized and crystallographically characterized. They are the first reported lanthanide-TOCs coordinated with 1,10-phenanthroline (phen) and 2,2'-bipyridine (bpy) as photoactive ligands, Eu2Ti4O6(phen)2(pa)10 (1) (pa = propionate), Eu2Ti4O6(bpy)2(pa)10 (2), and Eu2Ti4O6(phen)2(MA)10 (3) (MA = methacrylate). Benefitting from the photoactive antenna ligands and the rigid cluster structures, these clusters showed bright red luminescence with quantum yield in the range of 60-80% and long lifetime up to 3.0 ms. Unlike those physically mixed polymeric materials, the MA coordinated compound 3 can be self-polymerized to form a brilliant luminescent film. The film coated slide was used to develop a fluorescence sensor for biomolecule ascorbic acid (AA). The low detection limit and reusable properties suggest great potential for such EuTOC films in real applications.

Antineoplastic Mitoxantrone Monitor: A Sandwiched Mixed Matrix Membrane (MMM) Based on a Luminescent MOF-Hydrogel Hybrid.

A sandwiched mixed matrix membrane (MMM) based on a metal-organic framework-hydrogel hybrid exhibits eximious performance in the detection of mitoxantrone. Parts per billion-level sensitivity and good selectivity in serum among other analogous antineoplastics have been achieved. This flexible MMM can be used for point-of-care testing drugs in a biological medium.

Supramolecular Approach for Fine-Tuning of the Bright Luminescence from Zero-Dimensional Antimony(III) Halides.

Halides of ns2 metal ions have recently regained broad research interest as bright narrowband and broadband emitters. Sb(III) is particularly appealing for its oxidative stability (compared to Ge2+ and Sn2+) and low toxicity (compared to Pb2+). Square pyramidal SbX5 anion had thus far been the most common structural motif for realizing high luminescence efficiency, typically when cocrystallized with an organic cation. Luminescent hybrid organic–inorganic halides with octahedral coordination of Sb(III) remain understudied, whereas fully inorganic compounds show very limited structural engineerability. We show that the host–guest complexation of alkali metal cations with crown ethers fosters the formation of zero-dimensional Sb(III) halides and allows for adjusting the coordination number (5 or 6). The obtained compounds exhibit bright photoluminescence with quantum yields of up to 89% originating from self-trapped excitons, with emission energies, Stokes shifts, and luminescence lifetimes finely-adjustable by structural engineering. A combination of environmental stability and strong, intrinsic temperature-dependence of the luminescence lifetimes in the nanosecond-to-microsecond range nominate these compounds as highly potent luminophores for remote thermometry and thermography owing to their sensitivity range of 200–450 K and high specific sensitivities of 0.04 °C–1.

Multicolor-emitting luminescent Y2O3:RE3+@SiO2-[RE3+(β-diketone)3] core@shell hybrids featuring dual RE3+ activator centers

Luminescent inorganic-organic hybrids find several applications such as in multifunctional devices or in bioimaging. In this regard, through a step-by-step process, inorganic-organic [email protected] hybrids based on spherically-shaped Y2O3:Eu3+@SiO2-[Tb(acac)3(Salen)] or Y2O3:Tb3+@SiO2-[Eu(dbm)3(Salen)] particles with diameter of 170 nm were fabricated from Y2O3:RE3+ (RE3+ = Eu3+ or Tb3+) coated with a layer of SiO2 (2.7 nm), that was amino-functionalized, followed by imino-functionalization to get Salen ligands to which were finally bonded to [RE(β-diketonate)3] complexes (β-diketonate = acetylacetonate, acac, or dibenzoylmethanate, dbm). The [email protected] architecture of the hybrids was confirmed by X-ray diffraction, FTIR and TEM. By changing the excitation pathways, the overall emitted color of both hybrids is tuned from green (Tb3+ emission) to red spectral region (Eu3+ emission), crossing the white color emission region due to the combination of the Eu3+, Tb3+ and Salen emissions. As an additional and interesting find, no energy transfer from the RE3+ in the core to the other RE3+ on the particle surface takes place, avoiding the quenching of both RE3+ luminescence. Therefore, the high 5D0 state quantum efficiency of Eu3+ (68%) and the multicolor emission qualify the hybrids for future photonic applications in multifunctional devices or in bioimaging.

Synthesis, spectroscopic and photoluminescence studies of novel Eu3+ nanophosphor complex as fluorescent sensor for highly sensitive detection of latent fingerprints and anti-counterfeiting

Great attention has been paid to synthesize novel luminescent hybrid Eu(Thiol)Phen Nanophosphor complex; where (Thiol) = (E)-2-hydroxy-N/-((thiophen-2-yl)methylene)benzohydrazide and (Phen) = 1,10-phenanthroline as co-ligand. Properties like structure, morphology and optical characters were investigated. The results revealed that binary ligand acts as monoanionic tridentate through N-atom, O-atom and S-atom as donor sites. The secondary ligand (Phen) acting as bidentate through two (CN)pyridine groups. TEM image of ternary hybrid Eu(Thiol)Phen phosphor complex was cleared aggregated hybrid morphologies between sheet and rode shapes and their crystal sizes were in nanodomain. A pure red emission of Eu3+ Nanophosphor complex with long lifetime value was obtained, under harmless UVA, UVB and UVC. Optimized photoluminescence (PL) of Nanophosphor complex effectively developed as a novel sensing material for the visualization of latent fingerprints (LFPs) from various forensic relevant materials, including non-porous and porous of multi-color surfaces as well as security ink applications.

Novel luminescent europium-centered hybrid material covalently grafted with organically modified titania via 2-substituted imidazophenanthroline for fluorescence sensing

By employing a rational approach, we prepared a novel kind of luminescent europium-centered hybrid material named Eu(tta)3NCP-TiO2. The resulting material was characterized by FT-IR spectra, SEM, X-ray diffraction, thermogravimetric analysis, and photoluminescence spectra. The hybrid material features the combined advantages of the europium complex and the titania host, exhibiting not only good thermostability, but also long luminescence lifetime. Owing to the excellent luminescence of this material, the application in detecting organic small molecule solvents and metal ions was explored systematically. Significantly, Eu(tta)3NCP-TiO2 exhibits superior detection for nitrobenzene molecule and Cu2+ ion in DMF (N,N-dimethylformamide) medium. Furthermore, the limit of detection (LOD) of Eu(tta)3NCP-TiO2 for nitrobenzene and Cu2+ ion can be counted as 5.593 × 10−5 and 9.566 × 10−5 mol/L, respectively. The results demonstrate that Eu(tta)3NCP-TiO2 can serve as an efficient fluorescence probe for the detection of sensing of nitrobenzene and Cu2+ ion.

Luminescent inorganic–organic hybrid with tunable red light emissions by neutral molecule modification

Various luminescent organic-inorganic metal halide hybrid materials focus on fluorescence modulation. The commonly method to tunes the luminescence is usually via either modifying the structure of the inorganic anionic or the cation moiety. We here show the first time to modulate the fluorescent emission by inserting neutral organic molecules. The synthesis, crystal structure and optical properties of three organic-inorganic hybrids, [HEV][BiCl5] (1), [MV]3[Bi4Cl18]·[C16H10] (2) and [MV]3[Bi4Cl18]·[C20H12] (3) ([HEV]2+ = N-proton-N′-ethyl-4,4′-bipyridinium, [MV]2+ = N,N′-dimethyl-4,4′-bipyridinium) were demonstrated. The compounds contain MV2+ cations, bismuth (III)-chloro anions and pyrene or perylene molecules achieve fluorescence modulation upon the insertion of neutral molecules.

Recent Progress on Luminescent Metal-Organic Framework-Involved Hybrid Materials for Rapid Determination of Contaminants in Environment and Food.

The high speed of contaminants growth needs the burgeoning of new analytical techniques to keep up with the continuous demand for monitoring and legislation on food safety and environmental pollution control. Metal-organic frameworks (MOFs) are a kind of advanced crystal porous materials with controllable apertures, which are self-assembled by organic ligands and inorganic metal nodes. They have the merits of large specific surface areas, high porosity and the diversity of structures and functions. Latterly, the utilization of metal-organic frameworks has attracted much attention in environmental protection and the food industry. MOFs have exhibited great value as sensing materials for many targets. Among many sensing methods, fluorometric sensing is one of the widely studied methods in the detection of harmful substances in food and environmental samples. Fluorometric detection based on MOFs and its functional materials is currently one of the most key research subjects in the food and environmental fields. It has gradually become a hot research direction to construct the highly sensitive rapid sensors to detect harmful substances in the food matrix based on metal-organic frameworks. In this paper, we introduced the synthesis and detection application characteristics (absorption, fluorescence, etc.) of metal-organic frameworks. We summarized their applications in the MOFs-based fluorometric detection of harmful substances in food and water over the past few years. The harmful substances mainly include heavy metals, organic pollutants and other small molecules, etc. On this basis, the future development and possible application of the MOFs have prospected in this review paper.

Blending Ionic and Coordinate Bonds in Hybrid Semiconductor Materials: A General Approach toward Robust and Solution-Processable Covalent/Coordinate Network Structures.

Inorganic semiconductor materials are best known for their superior physical properties, as well as their structural rigidity and stability. However, the poor solubility and solution-processability of these covalently bonded network structures has long been a serious drawback that limits their use in many important applications. Here, we present a unique and general approach to synthesize robust, solution-processable, and highly luminescent hybrid materials built on periodic and infinite inorganic modules. Structure analysis confirms that all compounds are composed of one-dimensional anionic chains of copper iodide (CumIm+22-) coordinated to cationic organic ligands via Cu-N bonds. The choice of ligands plays an important role in the coordination mode (μ1-MC or μ2-DC) and Cu-N bond strength. Greatly suppressed nonradiative decay is achieved for the μ2-DC structures. Record high quantum yields of 85% (λex = 360 nm) and 76% (λex = 450 nm) are obtained for an orange-emitting 1D-Cu4I6(L6). Temperature dependent PL measurements suggest that both phosphorescence and thermally activated delayed fluorescence contribute to the emission of these 1D-AIO compounds, and that the extent of nonradiative decay of the μ2-DC structures is much less than that of the μ1-DC structures. More significantly, all compounds are remarkably soluble in polar aprotic solvents, distinctly different from previously reported CuI based hybrid materials made of charge-neutral CumXm (X = Cl, Br, I), which are totally insoluble in all common solvents. The greatly enhanced solubility is a result of incorporation of ionic bonds into extended covalent/coordinate network structures, making it possible to fabricate large scale thin films by solution processes.

Light-Emitting Lanthanide Periodic Mesoporous Organosilica (PMO) Hybrid Materials.

Periodic mesoporous organosilicas (PMOs) have a well ordered mesoporous structure, a high thermal and mechanical stability and a uniform distribution of organic functionalities in the pore walls. The organic groups allow PMOs to be modified and functionalized by using a wide range of organic reactions. Since their first report in 1999, PMOs have found a vast range of applications, such as for catalysis, adsorbents, low-k films, biomedical supports and also for optical applications. Optical applications are very interesting as PMOs offer the possibility of designing advanced luminescent hybrid materials comprising of organic components, yet with much higher stability and very good processability. Despite their promising possibilities, the optical properties of pristine PMOs and PMOs grafted with d-metal or f-metal ions and complexes have been explored less frequently. In this review, we aimed to overview the exciting light emitting properties of various reported lanthanide PMO hybrid materials and interest the reader in this promising application for lanthanide PMO materials.

Synthesis of hybrid materials by immobilizing para-aminobenzoic acid complexes of Eu3+ and Tb3+ in zeolite Y and their luminescent properties

Two new lanthanide containing zeolite Y based luminescent hybrid materials were synthesized and characterized. Exchange of Na+ from zeolite Y with lanthanide ions (Eu3+ or Tb3+) was carried out by ultrasonication and annealing. Para-amino benzoic acid was introduced to the ion exchanged zeolite Y to form complex with the lanthanide ion. Characterizations of the materials were carried out using IR spectroscopy, PXRD, SEM, UV–Vis absorption spectroscopy, TG–DTA and DSC analysis. Luminescence properties of these materials were studied using photoluminescence spectroscopy. Complex formation inside the zeolite cage increased the luminescence efficiency of the lanthanide ions through antenna effect. Tb3+ containing hybrid material showed efficient energy transfer due to the optimal energy level matching of the triplet level of ligand and the emissive level of Tb3+. Zeolite Y structure acts as a protective barrier against the degradation of organic part as is evident from the high thermal stability of the materials.

Photochromic and luminescent switchable iodoargentate hybrids directed by solvated lanthanide cations.

Four iodoargentate hybrids, [Eu(DMSO)8]2[Ag2I5][Ag5I8] (1), [Eu(DMSO)8][Ag7I10] (2), [Tb(DMSO)8]2[Ag2I5][Ag5I8] (3) and [Tb(DMSO)8][Ag6I9] (4) (DMSO = dimethyl sulfoxide), have been rationally synthesized, which display simultaneous photochromic and luminescent switchable performances. Photochromism is due to the photolysis of iodoargentate anions and the consequent generation of Ag0 particles with surface plasmon resonance (SPR) absorption. Meanwhile, luminescent switchable performance is ascribed to intermolecular fluorescence resonance energy transfer (FRET) from fluorescent solvated lanthanide cations to photochromic iodoargentate anions.

Luminescent hybrid coatings prepared by a sol–gel process for a textile-based pH sensor

Luminescent hybrid materials which contain fluorene and stilbene based fluorophores were coated onto cotton fabrics to design textile-based pH sensors.

Engineering of luminescent graphene quantum dot-gold (GQD-Au) hybrid nanoparticles for functional applications

Graphene quantum dots (GQDs) possess excellent optical and electrical properties that can be used in a wide variety of application. Synthesis of hybrid nanoparticles with GQDs have been known to improve the properties further. Therefore, in this method, graphene quantum dots –gold (GQD-Au) hybrid nanoparticles were synthesized using GQDs which reduces HAuCl4.3H2O to Au nanoparticles on its surface at room temperature. The GQDs with self-passivated layers were synthesized by microwave assisted hydrothermal method using glucose as a single precursor. The synthesis process does not involve the use of harmful chemicals. The whole synthesis process of GQD and GQD-Au hybrid nanoparticles takes only five minutes. The synthesized GQDs have been extracted using citrate in order to increase the stability of the hybrid nanoparticles for up to four weeks. The size of the synthesized GQD-Au hybrid nanoparticles is in the range of 5–100 nm and were found to be luminescent under UV-A illumination. The merit of the following method over other synthesis techniques include its rapidity, ease of preparation, and no requirement of elaborate synthesis procedures and/or harmful chemicals. The GQD-Au hybrid nanoparticles can be used in several applications such as luminescent coatings for glass and windowpanes for automobiles, etc. The reducing property of GQDs can further be utilized for the reduction of various metal salts (AgNO3) and organic dyes (methylene blue and methyl orange).. It presents a method/protocol-development of the luminescent GQD-Au hybrid particles of size ~ 5–100 nm.. The GQD-Au hybrid particles find potential applications in luminescent coating applications.

Tunable yellow–green emitting cyclotriphosphazene appended phenothiazine hydrazone hybrid material: synthesis, characterisation, photophysical and electrochemical studies

A novel tunable yellow–green emitting inorganic–organic luminescent hybrid molecule, CTP-PTZ, an assembly of six units of the PTZ hydrazone Schiff base on the periphery of inorganic heterocycle cyclotriphosphazene, is reported.

Synthesis of a novel β-cyclodextrin-functionalized Fe3O4/BaMoO4:Dy3+ magnetic luminescent hybrid nanomaterial and its application as a drug carrier.

Magnetic luminescent hybrid nanoparticles Fe3O4/BaMoO4:Dy3+ (MLHNPs) were successfully synthesized by the co-precipitation method using ethylene glycol. The MLHNPs are functionalized with β-cyclodextrin (CD) using 3-aminopropyl triethoxysilane (APTES). The surface functionalization of nanoparticles and their conjugation have been confirmed via powder XRD, FTIR, HRTEM, and PL analyses. The feasibility of functionalized MLHNPs as nanocarriers for hydrophobic drugs (triazole derivatives) was verified by studying the uptake and release profile using a triazole derivative as a hydrophobic drug. In addition, the photoluminescence spectroscopy results confirmed the optical imaging capability of MLHNPs. The outcomes of loading and release disclose that this system is likely to be a suitable tool as a hydrophobic drug carrier.

Dry Mechanochemical Synthesis of Highly Luminescent, Blue and Green Hybrid Perovskite Solids

AbstractA simple method to obtain bright photoluminescent wide bandgap mixed‐halide 3D perovskites is reported. The materials are prepared by dry mechanochemical synthesis (ball‐milling) starting from neat binary precursors, and show enhanced photoluminescence upon the addition of an adamantane derivative in the precursors' mixture. The structural characterization suggests that the additive does not participate in the crystal structure of the perovskite, which remains unvaried even with high loading of amantadine hydrochloride. By simple stoichiometric control of the halide precursors, the photoluminescence can be finely tuned from the UV to the green part of the visible spectrum. Photoluminescence quantum yields as high as 29% and 5% have been obtained for green‐ and blue‐emitting perovskite solids, even at very low excitation densities.

Luminescent Hybrid Materials Based on Polymers of Poly(Alpha-Fluoroacrylates) Doped with Tb(III) Complex

This study is devoted to the development of efficient luminescent hybrid materials excited by UV radiation and featuring narrow luminescence lines as well as light, humidity, and temperature resistance. As a luminescent material, a terbium ion coordination compound introduced into the matrix of an organofluorine polymer is used. It has been shown that efficient excitation transfer to electronic levels of the terbium ion can be achieved by proper ligand selection. The polymer matrix material does not affect the luminescence properties of the Tb(III) coordination compound.