Luminescent Hybrid Materials Research Articles

Luminescent Hybrid Material Based on the Europium(III)–β‐Diketone Complex Doped with Smectite

Luminescent Hybrid Material Based on the Europium(III)–β‐Diketone Complex Doped with Smectite

Electrochromic windows based on luminescent acrylate/ionosilicas

AbstractPoly(methyl methacrylate) (PMMA)-based composite films doped with lanthanide-doped sol–gel derived imidazolium-based ionosilicas (IS-Ln) were recently proposed as active layers of luminescent down shifting (LDS) layers, but subsequent work demonstrated also their potential as electrolytes for electrochromic devices (ECDs) with foreseen application in smart windows of energy-efficient buildings. Nevertheless, some challenges remained to be addressed in the latter devices, the most critical one being the poor solubility of PMMA in the ionic liquid used in the formulation of these materials. To avoid this drawback, in the present work we propose novel lanthanide-containing acrylate/ionosilicas (AC/IS-Ln, Ln = Tb3+, Eu3+). The transparent, homogeneous, and luminescent hybrid materials synthesized are characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, atomic force microscopy, contact angle measurements, ionic conductivity, and photoluminescence spectroscopy. Optimized samples are successfully employed as electrolytes in luminescent ECD prototypes. The ECD device doped with AC/IS-Eu shows good cycling stability with reproducible bleaching/coloring over 50 chronoamperometry cycles, high coloration efficiency (CE) values CEin/CEout in the visible (−89/+98 cm2 C−1), and near-infrared (−126/138 cm2 C−1) spectral regions, and outstanding memory effect. Graphical Abstract

Orbital Engineering Mediated by Cation Conjugation in Luminescent Uranyl-Organic Hybrid Materials.

A series of compounds of the form [HAr]2 [UO2 X4 ] is reported here, wherein Ar is systematically varied between pyridine (1-X), quinoline (2-X), acridine (3-X), 2,5-dimethylpyrazine (4-X), quinoxaline (5-X), and phenazine (6-X), and X=Cl or Br. With greater conjugation in the organic cation, a larger quenching in uranyl luminescence is observed in the solid state. Supporting our luminescence experiments with computation, we map out the potential energy diagrams for the singlet and triplet states of both the [HAr]+ cations and [UO2 Cl4 ]2- anion in the crystalline state, and of the assembly. The distinct energy transfer pathways in each compound are discussed.

Polyarylether-based COFs coordinated by Tb3+ for the fluorescent detection of anthrax-biomarker dipicolinic acid.

In this study, a rare-earth hybrid luminescent material (lanthanide@COF) was constructed for the detection of a biomarker for anthrax (dipicolinic acid, DPA). JCU-505-COOH was prepared by the hydrolysis of the cyano group in JCU-505 via a post-synthetic modification strategy, then the carboxyl groups in JCU-505-COOH coordinated with Tb3+ ions, similar to pincer vising nut. The prepared Tb3+@JCU-505-COOH exhibited a turn-on response toward DPA, which allowed the lanthanide@COF to serve as a fluorescence sensor with excellent selectivity and high sensitivity (binding constant Ka = 3.66 × 103). The fluorescent probe showed satisfactory performance for the determination of DPA in saliva and urine with a detection limit of 0.6 μM. Moreover, we established a facile point-of-care testing (POCT) using the Tb3+@JCU-505-COOH-based fluorescent test paper together with a smartphone for the initial diagnosis of anthrax. As expected, Tb3+@JCU-505-COOH showed great potential for the rapid screening of anthrax due to low cost, simple operation, and wide applicability.

Photoluminescent Layered Crystal Consisting of Anderson-Type Polyoxometalate and Surfactant toward a Potential Inorganic-Organic Hybrid Laser.

The hybridization of inorganic and organic components is a promising strategy to build functional materials. Among several functions, luminescence is an important function which should be considered for practical usage. Inorganic-organic hybrid luminescent materials have been investigated as phosphors, sensors, and lasers. Organic luminescent centers such as dye molecules have often been hybridized with inorganic matrices. Polyoxometalate anions (POMs) are effective inorganic luminescent centers due to their luminescent properties and structural designability. However, most luminescent POM components are limited to lanthanide-based POMs. In this report, a photoluminescent inorganic-organic hybrid crystal based on a non-lanthanide POM was successfully synthesized as a single crystal. Anderson-type hexamolybdochromate ([CrMo6O18(OH)6]3-, CrMo6) anion exhibiting emission derived from Cr3+ was utilized with n-dodecylammonium ([C12H25NH3]+, C12NH3) surfactant cation to obtain a photoluminescent hybrid crystal. The grown single crystal of C12NH3-CrMo6 comprised a distinct layered structure consisting of inorganic CrMo6 layers and interdigitated C12NH3 layers. In the CrMo6 layers, the CrMo6 anions were associated with water molecules by hydrogen bonding to form a densely packed two-dimensional network. Steady-state and time-resolved photoluminescence spectroscopy revealed that the C12NH3-CrMo6 hybrid crystal exhibited characteristic emission from the CrMo6 anion. Preliminary lasing properties were also observed for C12NH3-CrMo6, which shows the possibility of using the C12NH3-CrMo6 hybrid crystal as an inorganic-organic hybrid laser.

Silicon‐linked polyethylene glycol‐polyethylene terephthalate (PEG‐PET) nanostructures loaded with Eu3+‐complexes for hybrid luminescent PET materials

AbstractIn this work, innovative hybrid poly(ethylene terephthalate) (PET) materials with strong luminescence were successfully synthesized by doping PET with silicon‐linked poly(ethylene glycol)‐PET copolymer nanostructures either with (Si‐PEG‐PET) or with (ETP@Si‐PEG‐PET) luminescent Eu3+‐complexes. The chemical properties and nanostructures of the hybrid materials were characterized by Fourier‐transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, x‐ray photoelectron spectroscopy, and high‐resolution transmission electron microscopy. PET composites ranging from 0.25 to 4 wt% silicon additive were prepared by the melt blending method. The crystal properties, mechanical properties, and fluorescence properties of the composites were systematically studied by differential scanning calorimetry, x‐ray diffractometry, tensile testing, and fluorescence spectrometry. When the addition of Si‐PEG‐PET or ETP@Si‐PEG‐PET was 0.75 wt%, the relative crystallinity and maximum tensile strength increase substantially. Moreover, the fluorescence intensity of hybrid luminescent PET materials is the strongest at 0.75 wt% loading. ETP@Si‐PEG‐PET not only endows PET polyester with stronger fluorescence properties and mechanical properties but also acts as an effective nucleation additive for PET.Highlights Silicon‐linked poly(ethylene glycol)‐poly(ethylene terephthalate) (PEG‐PET) nanostructures generate hybrid luminescent PET materials. ETP@Si‐PEG‐PET improves the crystallization rate and crystallinity of PET. The composite with 0.75% addition showed the best fluorescence performance. Three‐dimensional‐grid structure of ETP@Si‐PEG‐PET enhances the mechanical property of PET.

Quercetin and 5-Fu Loaded Chitosan Nanoparticles Trigger Cell-Cycle Arrest and Induce Apoptosis in HCT116 Cells via Modulation of the p53/p21 Axis.

Nanoparticles (NPs) are encapsulating agents that exist in the nanometer range. They can be classified into different classes based on their properties, shapes, or sizes. Metal NPs, fullerenes, polymeric NPs, ceramic NPs, and luminescent nanoporous hybrid materials are only a few examples. This study explored the anticancer potential of quercetin and 5-fluorouracil-encapsulated chitosan nanoparticles (CS-5-FU-QCT NPs). The nanoparticles were prepared by ionic gelation, and their efficacy and mechanism of action were examined. CS-5-FU-QCT NPs were characterized using dynamic light scattering (DLS), atomic force microscopy (AFM), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR); cytotoxicity was analyzed using an MTT assay. Cells were treated with CS-5-FU-QCT NPs and incubated for 12, 24, and 36 h, and apoptosis analysis (using Annexin V/FITC), cell-cycle analysis, Western blotting, and confocal microscopic analysis were performed. Biophysical analysis revealed that the CS-5-FU-QCT NPs fall in the range of 300-400 nm with a near-spherical shape. The in vitro drug release profile indicates sustained release of drugs over a period of about 36 h. The cytotoxicity of CS-5-FU-QCT NPs was more prominent in HCT116 cells than in other cancer cells. This particular nanoformulation caused G0/G1 phase cell-cycle arrest in HCT116 cells and induced intracellular ROS generation, thereby causing apoptosis. It also downregulated Bcl2, cyclin D1, and Cdk4 and upregulated BAX, p53, and p21, causing cell-cycle arrest and apoptosis. In summary, CS-5-FU-QCT NPs hindered proliferation of HCT116 cells via ROS generation and altered the expression of key proteins in the p53/p21 axis and apoptotic machinery in a time-dependent manner.

Eu3+ Coordinated Hyperbranched Polysiloxane with Multicolor Emission and Long Fluorescence Lifetime†

Comprehensive SummaryHyperbranched polysiloxanes have attracted increasing interest due to their unique fluorescence properties. However, the relatively short emission wavelength and low fluorescence lifetime are still the main obstacles to their broader application. In this study, we first synthesized a β‐diketone contained hyperbranched polysiloxane with excitation‐dependent multicolor emission. Further through the coordination of HBPSi‐NMDEA with Eu3+ ion, a hybrid luminescent material was prepared. It exhibited not only aggregation‐induced red emission at 613 nm, but also a long fluorescence lifetime of 681.45 μs. Particularly, it showed highly sensitive reversible fluorescence response to temperature variation, thus displaying the potential to be used in fluorescence temperature detection.

New Strategy for Optimizing the Properties of Copper Halide Organic-Inorganic Hybrid Lighting-emitting Materials.

Copper(I) halide organic-inorganic hybrid luminescent materials have many advantages, such as diverse structure, facile synthesis, high luminescent efficiency, tunable optical performance, etc., and show a broad application prospect in energy-saving lighting, display and other fields. However, compared with commercial rare-earth-metal-based phosphors, the reported hybrids generally suffer from poor stability and low luminescent efficiency, which are the bottleneck problem of their practical application. With the aim of developing high-performance organic-inorganic hybrid luminescent materials, a new synthesis strategy has been reported. This strategy can systematically design and synthesis copper(I) halide ionic hybrid structures by combining the covalent bonding and ionic bonding between inorganic and organic components into one structure, and use their synergistic effect to optimizing their properties. This design method is expected to develop high-performance organic-inorganic hybrid luminescent materials, promote the in-depth understanding of this field, and provide new ideas for the optimization of other types of hybrid materials.

Competing Energy Transfer in Two-Dimensional Mn2+-Doped BDACdBr4 Hybrid Layered Perovskites with Near-Unity Photoluminescence Quantum Yield.

Two-dimensional (2D) hybrid layered perovskites (HLPs) have attracted extensive attention due to their excellent optoelectronic properties. Herein, we successfully prepared high-quality Mn-doped BDACdBr4 (BDA = NH2(CH2)4NH2, butylene diammonium) HLP single crystals (SCs). The incorporation of Mn2+ ions modulates the electronic band structure of BDACdBr4 perovskites and tailors the energy transfer process of excited states. A near-unity photoluminescence (PL) quantum yield of 96% from the Mn2+ emission at 608 nm is achieved. Excitation wavelength-dependent spectroscopic characterizations help to clarify the energy transfer mechanism of Mn-doped BDACdBr4, in which competing PL from the 3Eg → 1A1g transition of Cd2+ and the 4T1(G) → 6A1(S) transition of Mn2+ dopants is observed. Temperature-dependent PL spectroscopic characterizations indicate that the efficient energy transfer from BDACdBr4 perovskite host to Mn2+ dopants requires thermal activation to overcome a potential barrier. This work provides new insight into the photophysics and optical properties of 2D HLPs, especially the influence of Mn2+ doping on competing energy transfer in hybrid luminescent materials.

Water Processable Bioplastic Films from Functionalized Protein Fibrils

AbstractA combination of mechanochemistry and aqueous self‐assembly is employed to prepare protein nanofibrils (PNFs) functionalized with perylene diimide (PDI) dyes. These materials are then mixed with poly(vinyl alcohol) (PVA) and casted into bioplastic films. The functionalization process not only results in luminescent hybrid materials, but the presence of the dye modifies the physical properties of the PNFs. Films formed from PNFs functionalized with PDIs display anisotropic organization, which enables emission of polarized light. Crucially, the presence of PDI dyes improves the stability of PNF‐PVA films in water and moreover the films are processable when wet. By applying water, films can be glued together or self‐healed by applying water. Mechanochemical methodology can thus be employed for modifying properties of protein materials. This represents a new highly flexible and novel strategy for tuning both properties and functionality of protein materials.

Luminescent Hybrid Material Based on Boron Organic Phosphor and Silica Aerogel Matrix.

A new luminescent hybrid material based on silica aerogel and a boron-containing coordination compound with 8-hydroxyquinoline was created, and its physicochemical and spectral-luminescent characteristics were studied. A simple scheme for the synthesis of a hybrid luminescent material was developed. Simultaneously with the synthesis of the aerogel, the formation of a boron-containing phosphor was carried out using an isopropanol solution of boric acid and 8-hydroxyquinoline. Using in situ luminescent measurements, the mechanisms of the formation of boron-based luminescent complexes in isopropanol and tetrahydrofuran media were established. Both hydrophilic and hydrophobic silica aerogels were tested as matrices for the hybrid material. The formation of a thin layer of a boron-containing coordination luminescent compound on the highly developed surface of the SiO2 aerogel made it possible to strongly stabilize the aerogel structure and noticeably increase the thermal stability of the synthesized hybrid material.

Building hybrid luminescent materials: Understanding stacking modes in aggregate structure to emission modulation

Two charge transfer (CT) complexes A1 and A2 with tunable emissions were explored by diluting anthracene functionalized stilbene as donors with 1,2,4,5-tetracyanobenzene (TCNB) as the acceptor unit. The effect of substituent tailoring on the supramolecular packing and optical properties of the two CT products was accomplished by various solid-state characterization and theoretical calculations. It was found that these binary CT cocrystals exhibit two types of alternatively sandwiched face-to-face patterns (A1 (DADA), A2 (DAD··DAD), and red-shifted emissions relative to their monomers through π-π interactions accompanied by hydrogen bonds as indicated by the structural analysis. The two crystalline aggregates feature molar ratios of 1:1 or 1:2 and molecular packing-dependent emissions, induced by different dihedral angles attributed to the substituent effect, thereby leading to diverse π-π interactions and charge transfer effects respectively, which further results in tunable photophysical properties. These results suggest that the marriage of substituent engineering and cocrystal engineering is a promising molecular design strategy that will help to understand the relationship between emission property and molecular packing with the aim to guide further the development of novel organic solid luminescent materials.

Luminescent hybrid materials based on organic phosphors and fluorides in the PbF2-LaF3 system

Powder hybrid materials based on 8-hydroxyquinolate lithium organic phosphor and - LaF3 inorganic fluoride matrix PbF2 have been synthesized. Hybrid materials were obtained by co-precipitation from aqueous-alcoholic solutions with ammonium fluoride under various conditions - different concentrations of precursor solutions, Pb/La ratio, and the siquensy of reagents’ mixing. All obtained hybrid materials showed effective broadband luminescence in the region of 390-500 nm. The photoluminescence intensity during reverse deposition was found to be higher than during direct deposition for different concentrations of reagents.

Hybrid materials based on inorganic aerogel and organic luminophore

A new luminescent hybrid material based on inorganic aerogel “LightSil” (hereinafter referred to as HM-LS) has been fabricated. Organic phosphor has been directly synthesized from boron and 8-hydroxyquinolinol within the aerogel porous structure during its supercritical drying. Intercalation of various amounts of boron ions (0.01, 0.05 and 0.1 wt%) proceed at the gel aging stage. Synthesis and supercritical drying of materials were conducted in high pressure apparatus in a supercritical carbon dioxide medium at 120 bar pressure, 40°C and 500 g/h gas flow rate. The influence of ion amount on the luminescent, physical and structural characteristics of HM-LS were investigated. Analysis of the PL spectra showed that HM-LS with a boron ion concentration of 0.05 wt% has a highest photoluminescence intensity at a wavelength of 513 nm.

New Approach toward Dual-Emissive Organic-Inorganic Hybrids by Integrating Mn(II) and Cu(I) Emission Centers in Ionic Crystals.

Inorganic-organic hybrid luminescent materials have received great attention for their potential applications in a wide range of clean/renewable energy-related areas, including photovoltaics and solid-state lighting. Herein, we present a unique and general "Mn + Cu" approach by blending two earth-abundant luminogenic metals, manganese and copper, within a single ionic structure to construct a remarkable family of low-cost and multifunctional hybrid materials featuring dual emission, as well as triboluminescence and second-harmonic generation response. The novel hybrid materials are made of diphosphine dioxide-chelated [Mn(O∧O)3]2+ cations and various anionic [CuxIy](y-x)- clusters, ensuring manifestation of dual phosphorescence streamed from octahedral Mn2+ ions (605-648 nm) and iodocuprate anions (480-728 nm). Noteworthily, the relative ratio of the emission bands, and hence a resulting emission chromaticity, can be tuned in a wide range through modification of cluster [CuxIy](y-x)- modules. The structural diversity, enhanced robustness, and up to 100% luminescence quantum yield make the designed materials promising phosphors for lighting and sensing applications.

Detection of Cr(III), prometryn, and ibuprofen by hybrid Eu(III)–dipicolinate kaolinite luminescent sensor

Europium (III) was complexed on solids prepared by kaolinite functionalization with pyridine 2–carboxylic and pyridine 2,6–dicarboxylic acids; the luminescent properties of the obtained solids were analyzed for evaluating their application as luminescent sensors of prometryn, ibuprofen and chromium (III). The luminescent hybrid materials were characterized through powder X–ray diffraction, infrared absorption spectroscopy, thermal analysis, scanning electron microscopy, ultraviolet/visible absorption spectroscopy, energy dispersion and photoluminescence spectroscopy (excitation and emission) and lifetime measurements of the excited state. The materials proved to be promising, with quantum efficiencies of 31.16% and 45.18% for the samples functionalized with picolinic and dipicolinic acids, respectively. For the contaminant adsorption tests, the solid with picolinic acid showed better detection efficiency in a lower concentration range for chromium (III) than solids with dipicolinic acid, while both showed similar ranges for the organic contaminants.

LUMINESCENT SILICA AEROGEL DOPED BY COORDINATION SUBSTANCE OF BORON WITH 8-HYDROXYQUIONOLINE

A new luminescent hybrid material based on silica aerogel and a boron-containing coordination compound with 8-hydroxyquinoline has been created, and its physico-chemical and spectral-luminescent characteristics have been studied. A scheme for the synthesis of a hybrid luminescent material has been developed. The scheme eliminates the need for preliminary expensive synthesis of a high-purity organoelemental boron-containing phosphor. It has been established that aerogel hydrophobization significantly increases the stability of the luminescent characteristics of the hybrid material.

Luminescence properties of rare earth complexes bonded to novel mesoporous spherical hybrid materials

YVO4:Eu3+ phosphors have been widely used in optoelectronic integration fields of its chemical and thermal stability. However, the excitation spectrum band of VO43− is too narrow for high-efficiency luminescence, restricting its further development. Herein, flower-like and linear-like YVO4:Eu3+ hollow mesoporous spheres were synthesized and connected with Eu organic ligand, to obtain a new hybrid luminescent material. The characterization shows that the pores of microspheres are in size of about 2–50 nm, sticked with regular morphology, well crystallized, and in uniform distribution. The emission intensity of hybrid luminescent material is higher than that of single YVO4:Eu3+ and single Eu complexes realizing the purpose of mutually reinforcing luminescence. This paper provides a new idea to connect rare earth complexes for a new non-silicon-based mesoporous spherical matrix.

Unearth the Luminescence Potential of Metal-Organic Frameworks: Adopting a Feasible Strategy to Fabricate One Ratiometric Fluorescence Sensor for Monitoring Both 1-Hydroxypyrene and Cu2.

In this work, a novel luminescent hybrid material with double emission centers (Eu(TTA)0.2@9-1-UMOF) is successfully prepared, adopting a feasible design strategy. Initially, the second ligand 1,2,4-benzenetricarboxylic acid (H3BTC) is encapsulated based on a solid solution approach, which effectively improves the ligand-based emission intensity of the original LMOF and provides functional sites for introducing the second luminescent center; then, Eu3+ as the red emission source is loaded into the frameworks through a coordination post-synthetic modification method; finally, to balance the emission intensity at 613 nm (Eu3+) and 465 nm (1,4-naphthalenedicarboxylic acid (H2NDC)), 2-thenoyltrifluoroacetone (TTA) as a powerful antenna is introduced. Given the outstanding luminescence properties and structural stability of Eu(TTA)0.2@9-1-UMOF, it is further developed as a ratiometric sensor for detecting 1-hydroxypyrene (1-HP, the biomarker of polycyclic aromatic hydrocarbons (PAHs)) and Cu2+, which promotes the pre-diagnosis of human health. Notably, Eu(TTA)0.2@9-1-UMOF exhibits excellent selective recognition ability for both 1-HP and Cu2+ with high sensitivity (LOD = 4.06 × 10-6 mg/mL, 3.85 × 10-7 mol/L, respectively) and fast response speed. In addition, Eu(TTA)0.2@9-1-UMOF as a fluorescent probe shows great potential for the determination of 1-HP and Cu2+ in actual samples. More importantly, this work widens the road for the development of dual/multiple LMOF-based sensors for analytical applications.