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Photoluminescent (PL) solid with color tunability are in high demand for the development of large‐area display and illumination devices. With high transparency, high chemical stability, and mature fabrication, sol‐gel glass is an ideal solid matrix to obtain such materials by chromophore doping. However, it remains a big challenge to obtain sol‐gel glass with high luminous efficiency under a single excitation wavelength. Herein, the construction of highly luminescent sol‐gel glass enabled by Förster resonance energy transfer (FRET) is reported. Branched siloxane is used to modify naphthalene and BODIPY, which led to the formation of blue‐emitting donor (denoted as Si‐Nap) and green‐emitting acceptor (denoted as Si‐BODIPY), respectively. Efficient FRET occurs between Si‐Nap and Si‐BODIPY proved by spectral titration and lifetime measurements, with an energy transfer efficiency (ΦET) up to 97.9%. When RhB is added, it acts as a final acceptor that enables the occurrence of a sequential FRET from Si‐Nap to Si‐BODIPY and further to RhB. The overall energy transfer efficiency reaches 94%, and the fluorescence quantum yield exceeds 88%. By adjustment of the composition, color‐tunable sol‐gel glass is obtained with emergence of white‐emitting samples, opening potential applications in a variety of fields. [ABSTRACT FROM AUTHOR]

Two Schiff base binuclear Cu(II) compounds, [Cu2(L)2·(H2O)2]·2DMF (1) together with its coordination polymer (CP) [Cu2(L)2·(4,4′-bpy)2]n (2) (H2L is 4-hydroxy-3-((2-hydroxy-5-mercaptobenzylidene)amino)-2H-chromen-2-one and 4,4′-bpy is 4,4′-bipyridine), were generated under an identical experimental environment in the absence and existence of auxiliary ligand 4,4′-bpy. Fluorescence spectroscopy testing shows that the ligand-based blue fluorescence emission offers potential for application as a blue photoluminescent material. [ABSTRACT FROM AUTHOR]

Calcium molybdate (CaMoO 4) and Dy3+ doped CaMoO 4 (Dy3+ = 0.5, 1, 1.5, 2 and 2.5 at.%) nanoparticles were successfully obtained by mechanochemical approach. The influence of Dy3+ ion concentration on the structure, morphology, and photoluminescent properties were investigated. The CaMoO 4 and Dy3+ doped CaMoO 4 phases with tetragonal structure were completely prepared after 30 min milling time with applied milling speed of 850 rpm. TEM analysis shows that the synthesized samples consist of mainly spherical particles with narrow particle size distribution. According to both XRD and TEM analysis, the average particles size is below 40 nm. The UV–vis absorption spectra show one peak at 240–245 nm. The calculated optical band gap of pure CaMoO 4 is 3.96 eV and it decreases to 3.65 eV with increasing the concentration of Dy3+ ion up to 2.5 at %. The excitation spectra of the Dy3+-doped CaMoO 4 samples contain absorption peaks corresponding to the MoO 4 group and to the Dy3+ ion. The green and blue light emissions were observed for pure CaMoO 4 and Dy3+ doped CaMoO 4 samples under different wavelengths excitation (250 and 350 nm) typical for absorption of the host matrix. Emission spectra of all doped powders consist of the characteristic peaks of Dy3+ in the blue (∼480 nm) and yellow (∼575 nm) regions which are assigned to the 4F 9/2 → 6H 15/2 and 4F 9/2 → 6H 13/2 transitions, respectively. The weak peak at 660 nm also is observed due to 4F 9/2 → 6H 11/2 transition of Dy3+ ion. The highest photoluminescence emission intensity was detected when the sample is doped with 1.5 at.% Dy3+ concentration. It was found that the color coordinates (x and y) of 1.5 at.% and 2 at.% Dy3+-doped CaMoO 4 fall close to the white light region in the CIE diagram. The results indicate that the mechanochemically obtained Dy3+ doped CaMoO 4 nanoparticles can find application in different optical instruments. [ABSTRACT FROM AUTHOR]

The tetradentate ligand, merging a carbazole unit with high triplet energy and dimethoxy bipyridine, renowned for its exceptional quantum efficiency in coordination with metals like Pt, is expected to demonstrate remarkable luminescent properties. However, instances of tetradentate ligands such as bipyridine-based pyridylcarbazole derivatives remain exceptionally scarce in the current literature. In this study, we developed a tetradentate ligand based on carbazole and 2,3′-bipyridine and successfully complexed it with Pt(II) ions. This novel compound (1) serves as a sky-blue phosphorescent material for use in light-emitting diodes. Based on single-crystal X-ray analysis, compound 1 has a distorted square-planar geometry with a 5/6/6 backbone around the Pt(II) core. Bright sky-blue emissions were observed at 488 and 516 nm with photoluminescent quantum yields of 34% and a luminescent lifetime of 2.6 μs. TD-DFT calculations for 1 revealed that the electronic transition was mostly attributed to the ligand-centered (LC) charge transfer transition with a small contribution from the metal-to-ligand charge transfer transition (MLCT, ~14%). A phosphorescent organic light-emitting device was successfully fabricated using this material as a dopant, along with 3′-di(9H-carbazol-9-yl)-1,1′-biphenyl (mCBP) and 9-(3′-carbazol-9-yl-5-cyano-biphenyl-3-yl)-9H-carbazole-3-carbonitrile (CNmCBPCN) as mixed hosts. A maximum quantum efficiency of 5.2% and a current efficiency of 15.5 cd/A were obtained at a doping level of 5%. [ABSTRACT FROM AUTHOR]

Metasurface‐based optical elements offer a wide design space for miniature and lightweight optical applications. Typically, metasurface optical elements transform an incident light beam into a desired output waveform. Recent demonstrations of light‐emitting metasurfaces highlight the potential for directly producing desired output waveforms via metasurface‐mediated spontaneous emission. In this work, reciprocal finite‐difference time‐domain (FDTD) simulations and machine learning are used to enable the inverse design of highly unidirectional photoluminescent III‐Nitride quantum well metasurfaces capable of directive p‐, s‐, or combined p‐ and s‐ polarized emission at arbitrary angles. In comparison with previous intuition‐guided designs using the same quantum well architectures, the inverse design approach enables new polarization capabilities and experimentally demonstrated improvements in directivity of 54%. An analysis of ways in which the inverse design both validates and contradicts previous intuition‐guided design heuristics is presented. Ultimately, the combination of reciprocal simulations and efficient global optimization (EGO) grants remarkable improvements in emission directivity and results in full control over the polarization and momentum of emitted light, including simultaneous directional emission of s‐ and p‐polarized light. [ABSTRACT FROM AUTHOR]

The magnetic sensitivity of the ensemble NV centers is directly related to temperature. In this study, we systematically investigated the temperature dependence of photoluminescence properties and optical detection magnetic resonance in ensemble NV centers from 1.6 K to 300 K. The magnetic sensitivity of the ensemble NV centers increases with the temperature rising in the range of 1.6 K to 75 K due to changes in contrast and linewidth, reaching a minimum near 40 K. Furthermore, the decrease in sensitivity is attributed to laser intensity overload at low temperatures by studying the influence of laser power on contrast and linewidth. These results offer valuable insights into NV magnetic sensing applications. [ABSTRACT FROM AUTHOR]

A new Tb(III) complex based on 3‐pyridylacetic acid, [Tb(H(3‐PAA)2)(NO3)2] (1, 3‐PAA=3‐pyridylacetic acid), has been triumphantly prepared and structurally characterized. Complex 1 is a 1D chained structure linked by carboxylate groups of the 3‐PAA ligand, and its 2D supramolecular packing is controlled mainly by hydrogen‐bonds. The compound exhibits outstanding thermal stability and excellent stability under ethanol solutions. Moreover, compound 1 shows a strong solid‐state green‐emitting emission at room temperature, which demonstrates that the ligand can effectively sensitize the emission of the Tb(III) ion, and it can serve as a responsive sensing material for detecting the Fe3+ ion in ethanol solutions. [ABSTRACT FROM AUTHOR]

Preparation stable and continuous lanthanide metal–organic frameworks (Ln-MOFs) crystalline film coated on flexible substrate is a challenge for application. Herein a kind of novel nanoscale Eu-MOFs film on silk fabric for temperature sensing was successfully prepared. The silk fabric was coated with titanium dioxide (TiO2) via different atomic layer deposition (ALD) cycles, and then the Eu-MOFs can grow to nanoscale continuous film on the substrate. The composite was characterized by SEM, TEM, XPS, TG and PL. Fluorescence detection of temperature was also studied, and in a wide temperature range (77 K to 423 K), the fluorescence detection was sensitive and fitted to linear equation. In addition, the functional silk fabric exhibited different fluorescence detection behavior to temperature at different pH preparation conditions. At neutral preparation conditions, the fluorescence color of the functional silk fabric was dark yellow. The silk fabric exhibited rapid response in detection of temperature. At acidic preparation conditions, the fluorescence color was bright yellow, but it did not have detection effect. At alkaline preparation conditions, blue purple fluorescence was presented, and the temperature detection was also sensitive and fast. It is an effective method to obtain Ln-MOFs flexible film materials, and apply in the field of intelligent detection and wearing. [ABSTRACT FROM AUTHOR]

Green-emitting BaSrGd4O8: Er3+ nanophosphor is effectively synthesized using the solution combustion route. For crystallographic and morphological attributes, the samples have been characterized by various techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The atomic parameters are refined with the aid of Rietveld refinement realization, and the orthorhombic phase with space group Pnma (62) is confirmed. EDS analysis reveals the chemical composition while SEM and TEM techniques confirm the irregular shapes. On near-UV excitation, the luminescence spectrum presents a fair green emission at 18,083 cm−1 wavenumbers consistent with the electronic transition 4S3/2 → 4I15/2. Diffuse reflectance spectroscopy is used to examine the bandgap energy. Radiative lifetime, quantum efficiency, and rates of radiation-less electronic transitions are also examined. The CIE (Commission International de l'Eclairage) coordinates and hence the CCT (color coordinate temperature) values of the chromaticity plot are thus finalizing their potential contention in SSL (solid-state lighting) and other advanced optoelectronic applications. [ABSTRACT FROM AUTHOR]

Pr3+-ion doped YF3, LaF3, and GdF3 nanoparticles (NPs) were chemically prepared at a lower temperature (80 °C) to investigate the comparative physiochemical characteristics. X-ray diffraction profile of the nanoproducts exhibited the orthorhombic phase in YF3:Pr and GdF3:Pr NPs, whereas hexagonal structure was found in LaF3:Pr NPs with an estimated crystalline size 12, 23, and 15 nm, respectively. The unit cell constants for YF3:Pr (a = 6.340 Å, b = 7.269 Å, c = 4.317 Å, and unit cell volume = 198.97 (Å)3), LaF3:Pr (a = b = 7.171 Å, and c = 7.388 Å, and unit cell volume = 329.092 (Å)3) and GdF3:Pr (a = 6.465 Å, b = 7.008 Å, and c = 4.528 Å, and unit cell volume = 205.225 (Å)3) were considered to examine the influence of the dopant ions and the host ion's ionic radius on the crystal phase, and crystallinity. An orthorhombic phase GdF3:Pr NP sample revealed better thermal stability in comparison to the hexagonal phase LaF3:Pr NPs as received in the thermogravimetric outcomes. FTIR spectra exhibited the surface-fastened water molecules which promote the development of colloidal solution in aqueous solvents under the environmental conditions as achieved in absorption spectral analysis. Band gap energy was calculated from the UV/visible spectra to examine the optical behavior of the optically active NPs. The excitation and emission spectrums demonstrated the sharp excitation and emission transitions of the doped Pr3+ ion under excitation from the blue region. Comparatively, the emission and excitation transitions of the YF3:Pr NPs were dominant with respect to the orthorhombic GdF3:Pr and hexagonal LaF3:Pr NPs. YF3:Pr NPs are a useful host matrix for the loading of the activator Pr3+-ion for their use in luminescent phosphor material development. [ABSTRACT FROM AUTHOR]

Metal clusters have become increasingly important in various applications, with ligands playing a crucial role in their construction. In this study, we synthesized a bimetallic cluster, Ag6Cu8(C=CAr)14(DPPB)2 (Ag6Cu8), using a rigid acetylene ligand, 3,5‐bis(trifluoromethyl)phenylacetylide. Through single‐crystal structure characterization, we discovered that the butterfly‐shaped Ag2Cu2 motifs were subject to distortion due to steric hindrance imposed by the rigid ligand. These motifs assembled together through shared vertices and edges. Mass spectrometry analysis revealed that the primary fragments detected during electrospray ionization (ESI) testing corresponded to the Ag2Cu2 motifs. Furthermore, we conducted a comprehensive investigation of the cluster's solution properties employing 31P NMR, UV‐vis absorption, and photoluminescent measurements. In contrast to previously reported Ag/Cu bimetallic clusters protected by flexible ligands, Ag6Cu8 protected by rigid ligands exhibited intriguing room temperature fluorescence properties alongside excellent thermal stability. DFT calculations on Ag6Cu8 and Ag6Cu8 with the rigid aromatic ring removed revealed that the presence of the rigid aromatic ring can lower the electronic energy levels of the cluster, and reduce the energy gap from 4.05 eV to 3.45 eV. Moreover, the rigid ligand further suppressed the non‐radiative transition process, leading to room temperature fluorescence emission. [ABSTRACT FROM AUTHOR]

Blue phase liquid crystals (BPLCs) have significant potential in the field of liquid crystal displays (LCDs) and are proposed as potential next-generation of LCDs candidates. However, BPLCs do not emit light directly and need an extra backlight device. As a result, the blue phase liquid crystal display retains the disadvantages of low brightness and low energy efficiency, which remarkably limit its application. Recently, as a kind of novel fluorescent carbon nanomaterials, carbon dots (CDs) have captured considerable attention because of their excellent optical properties. Here, CDs were directly synthesized by a simple solvothermal method and introduced into BPLCs. By combining the excellent optical properties of CDs with the blue phase liquid crystal system, the photoluminescent blue phase liquid crystals (CDs-BPLCs) with self-photoluminescence are prepared. Meanwhile, the stability of BPLCs can be improved by CDs. Such CDs-BPLCs have enormous potential in the development of novel energy-saving display devices. [ABSTRACT FROM AUTHOR]

A series of lanthanide coordination polymers, i.e., [LnIII4(oba)6(H2O)9]·3H2O, where LnIII corresponded to EuIII (I), GdIII (II), TbIII (III), H2oba—4,4'-oxybis(benzoic acid), were synthesized using the rapid and facile microwave technique. They were structurally characterized and evaluated for use as photoluminescent probes in monosodium glutamate (MSG) detection. Possible interferences of amino acids were examined. Based on the devised ratiometric parameters, I showed viable responses to MSG. Linear calibration plot could be constructed over 10–100 mM with sensitivity, limits of detection and quantification of 33.2% mM, 1.3, and 4 mM, respectively. The constructed calibration plot could be used to determine concentrations of standard MSG solutions providing the percentage recoveries of 94–103%. The use of I for real soup samples was also attempted through the standard spiking approach. [ABSTRACT FROM AUTHOR]

In this present work, we have developed a dual-mode colorimetric and photoluminescent sensor based on nitrogen and sulphur-doped carbon dots (NSCDs) by cost-effective and simple hydrothermal method. Citric acid and glutathione were taken as the initial precursors. These NSCDs have shown excellent physiochemical and optical properties with high quantum yield. Here, it is more attractive one that when the prepared NSCDs were binded with glucose, the colour of the solution changes from colourless to blue under direct sunlight without the aid of an external ultraviolet lamp. Blue emission behaviour of these NSCDs was utilized for the selective binding confirmation and quantification of glucose. For selectivity, test various biomolecules have been analysed and the results showed high selectivity towards glucose molecules. 10 µM Glc showed emission of bright blue fluorescence with limit of detection at 0.26 μM concentration, and it was given by the photoluminescence behaviour based on 3σ/s criteria. This strategy has been applied for the visual detection of glucose in HepG2 cell which offers innovative perception into the biomedical applications of NSCDs to develop a way to sense glucose in clinical analysis. [ABSTRACT FROM AUTHOR]

Photoluminescent (PL) layers and electroluminescent (EL) systems have gained significant attention for their applications in constructing flat panels, screen monitors, and lighting systems. In this study, we present a groundbreaking approach to fabricating temperature sensors using barium-calcium zirconium titanate (BCZT) with thermo-optic properties, leading to the development of opto-thermal sensors for electric vehicle battery packs. We prepared zinc sulfide (ZnS) fluorescent films on BCZT ceramics, specifically two optimal compositions, BCZT0.85 (Ba0.85Ca0.15Zr0.1Ti0.9O3) and BCZT0.9 (Ba0.9Ca0.1Zr0.1Ti0.9O3), via the solid-state reaction method for the dielectric layer. The BCZT powders were calcined at varying temperatures (1200 and 1250 °C) and dwell times (2 and 4 h). The resulting phase formation and microstructure characteristics were analyzed using X-ray diffraction and scanning electron microscopy, respectively. Our investigation aimed to establish a correlation between the dielectric behavior and optical properties to determine the optimal composition and conditions for utilizing BCZT as thermal detectors in electric vehicle battery packs. All BCZT powders exhibited a tetragonal phase, as confirmed by JCPDS No. 01-079-2265. We observed an increase in the dielectric constant with higher calcining temperatures or longer dwell times. Remarkably, BCZT0.85 ceramic sintered at 1250 °C for 4 h displayed the highest dielectric constant of 15,342, establishing this condition as optimal for preparing the dielectric film with a maximum dielectric constant of 42. Furthermore, we investigated the temperature-dependent electroluminescence intensity of the samples, revealing a significant enhancement with increasing temperature, reaching its peak at 80 °C. Additionally, we observed a positive correlation between electroluminescence intensity and dielectric constant, indicating the potential for improved opto-thermal sensors. The findings from this study offer promising opportunities for the development of advanced opto-thermal sensors with potential applications in electric vehicle battery packs. Our work contributes to the expanding field of photoluminescent and electroluminescent systems by providing novel insights into the design and optimization of efficient and reliable sensors for thermal monitoring in electric vehicle technologies. [ABSTRACT FROM AUTHOR]

Colloidal semiconductor II–VI metal chalcogenide (ME) magic‐size clusters (MSCs) exhibit either an optical absorption singlet or doublet. In the latter case, a sharp photoluminescence (PL) signal is observed. Whether the PL‐inactive MSCs transform to the PL‐active ones is unknown. We show that PL‐inactive CdS MSC‐322 transforms to PL‐active CdS MSC‐328 and MSC‐373 in the presence of acetic acid (HOAc). MSC‐322 displays a sharp absorption at ≈322 nm, whereas MSC‐328 and MSC‐373 both have broad absorptions respectively around 328 and 373 nm. In a reaction of cadmium myristate and S powder in 1‐octadecene, MSC‐322 develops; with HOAc, MSC‐328 and MSC‐373 are present. We propose that the MSCs evolve from their relatively transparent precursor compounds (PCs). The PC‐322 to PC‐328 quasi‐isomerization involves monomer substitution, while monomer addition occurs for the PC‐328 to PC‐373 transformation. Our findings suggest that S dominates the precursor self‐assembly quantitatively, and ligand‐bonded Cd mainly controls MSC optical properties. [ABSTRACT FROM AUTHOR]

A new photoluminescent disc-like copper (II) metallomesogen of the type [CuL2] {H2L = 2,4-bis((E)-((4-(hexadecyloxy)phenyl)imino)methyl)phenol} have been synthesized. The compounds were characterized by elemental analyses, Fourier transform infrared spectroscopy (FTIR), 1H, 13C nuclear magnetic resonance (NMR), ultraviolet – visible spectroscopy (UV – Vis), thermogravimetric analysis (TGA) and high-resolution mass spectrometry. Mesomorphic behavior of the compounds was probed with the help of polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). The organization of the molecules in the mesophase was investigated by X-ray diffraction techniques. The ligand is non-mesogenic but the copper complex exhibited thermally stable columnar mesophases at about 86°C. The copper complex is a blue-light emitter both in solution and in the solid state. The Density Functional Theory (DFT) study was carried out using 6–31 G (d, p) basis set with unrestricted B3LYP level to obtain a stable, optimized structure, which revealed a distorted square-planar geometry for the copper complexes. [ABSTRACT FROM AUTHOR]

A two-dimensional threefold interpenetrated uranium-organic framework (UOF) has been synthesized by the solvothermal method with a highly luminescent response of various molecules. The structure of the compound is characterized by the single-crystal X-ray diffraction, [C27H17O11U] [C2H6N]·DMF·2H2O·(UTCPB), with a six-coordinated uranyl cation, further proved by the IR, TG and others tests. To explore the functional properties, photoluminescent, dye adsorption, and metal detecting properties have been also studied and discussed initially. The results showed that the compound exhibited some features in dye adsorption (RhB) and Ru3+ detection. [ABSTRACT FROM AUTHOR]

With the development of nanotechnology, fluorescent silicon nanomaterials have been synthesized and applied in various areas. Among them, silicon quantum dots (SiQDs) are a new class of zero-dimensional nanomaterials with outstanding optical properties, benign biocompatibility, and ultra-small size. In recent years, SiQDs have been gradually utilized for constructing high-performance fluorescent sensors for chemical or biological analytes. Herein, we focus on reviewing recent advances in SiQD-based fluorescent biosensors from a broad perspective and discussing possible future trends. First, the representative progress for synthesizing water-soluble SiQDs in the past decade is systematically summarized. Then, the latest achievement of the design and fabrication of SiQD-based fluorescent biosensors is introduced, with a particular focus on analyte-induced photoluminescence (fluorescence) changes, hybrids of SiQDs with other materials or molecules, and biological ligand-modification methods. Finally, the current challenges and prospects of this field are highlighted. [ABSTRACT FROM AUTHOR]

• We prepared three structurally different multi-peak emitting carbon dots using phenylenediamine isomers as precursors. • The fluorescence of all three carbon dots changes depending on the environment. • The multi-peak emission carbon dots have different fluorescence centers resulting from their different structures. Revealing the relationship between structure and optical properties of multi-peak emissive carbon dots (CDs) is important. Three types of multi-peak emission CDs were synthesized by one-step hydrothermal method with phenylenediamine (PD) isomers (o/m/p) and maleic anhydride serving as precursors. During the synthesis process, three PDs exhibited different microstructural and chemical states, resulting in various fluorescence emission centers. The multi-peak emission behavior of o-CDs and m-CDs is composed of molecular fluorophores and carbon core states, while that of p-CDs consists of surface states and carbon core states. These different fluorescence centers lead to diverse fluorescence behaviors of the CDs in different solvents and environments. This work inspires the clarification of the relationship between the structural and optical properties of multi-peak emissive CDs. [ABSTRACT FROM AUTHOR]

• Polyamides show solvochromic effects and large stokes shift. • Polyamides have specific fluorescent response to TNP and HCl. • Polyamides have excellent electrochromic and electrofluorescent properties. • The constructed electrochromic devices can display multiple colors. The pyrene group was directly connected to the triarylamine (TAA) unit through a benzene bridge via the Suzuki reaction to successfully prepare the diamine monomer. A series of new polyamides (PAs) based on TAA units were prepared by polycondensation. The PAs exhibited good solution processability and high thermal stability with the char yield in excess of 53 % at 800 °C in air atmosphere. In solvents with different polarities, these PAs showed solvatochromic effect and large stokes shift. Strongly photoluminescent PAs have a sensitive stimulus response to explosive and hazardous gas, and its fluorescence is easily turned off by the addition of trinitrophenol (TNP) and hydrogen chloride (HCl). And achieve fluorescence switching between exposure to HCl and ammonia (NH 3) gas. The PAs exhibited a reversible color response in the electrochemical oxidation process, with no significant degradation in current and transmittance after 200 cycles. The sandwich structure multicolor electrochromic device can achieve electrochromic performance applied by different voltages. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Bis-thiophene based dual mode sensor for Hg2+ (chromogenic) and Cu2+ (fluorogenic "turn on"). • Probe P1 selectively sense Hg2+ and Cu2+ ions with their lowest detection limits 1.29 µM and 39 nM respectively. • The designed probe P1 has excellent reversible and reproducible colorimetric and fluorometric methods. • Live cell imaging studies was performed for probe P1 in presence and absence of Cu2+ ion. In this work, we developed a fast and straightforward colorimetric and photoluminescent chemosensor probe (P1), featuring bis-thiophene-thiosemicarbazide moieties as its signaling and binding unit. This probe exhibited rapid sensitivity to Hg2+ and Cu2+ ions in a semi-aqueous medium, resulting in distinct colorimetric and photoluminescent changes. In the presence of Cu2+, P1 displayed an impressive 50-fold increase in photoluminescence (PL) at 450 nm (with excitation at 365 nm). The probe P1 formed a 1:1 complex with Hg2+ and Cu2+ ions, featuring association constant values of 4.04 × 104 M−1 and 1.25 × 103 M−1, respectively. P1 has demonstrated its efficacy in the analysis of real samples, yielding promising results. Additionally, the probe successfully visualized copper ions on a mouse fibroblast cell line (NIH3T3), highlighting its potential as an intracellular probe for copper ion detection. [ABSTRACT FROM AUTHOR]

Two dinuclear lanthanide complexes [Ln 2 (Hsal) 3 (NO 3) 6 ]·(C 2 H 5 N) 3 ·nH 2 O (Ln = Gd, Eu) were obtained and characterized. The complex Gd1 and Eu1 exhibit high thermal stability and excellent luminescent thermal stability. [Display omitted] Two new dinuclear lanthanide complexes [Ln 2 (Hsal) 3 (NO 3) 6 ]·(C 2 H 5 N) 3 ·nH 2 O (Ln = Gd, Eu) were synthesized with an aromatic carboxylic acid ligand (salicylate). Both complexes were extensively characterized by various techniques, including elemental analysis, infrared spectroscopy, powder X-ray diffraction, and X-ray single-crystal diffraction. The thermal behavior and photoluminescence properties of lanthanide complexes were investigated. It was found that the two complexes had good thermal stability even after heating at 180 °C for 1 h. Furthermore, the two complexes exhibit a unique luminescent thermal stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesized photoluminescent self-healing elastomers with 95.45% healing efficiency. • Photoluminescent characteristics are still present in 3D printed elastomers. • Printed sensors achieve segmented responses with high sensitivity and cyclic stability. • Sensors offer additional sensory information through changes in luminous intensity. Photoluminescent materials have garnered a lot of interest lately because of their many uses in chemical sensing, bio-detection, and optoelectronic devices. However, existing photoluminescent 3D printing materials exhibit deficiencies in mechanical properties, durability, and stability, hindering their adaptation to 3D printing of complex structures or stress-varying applications, while compromising the long-term stability of devices. To address these limitations, a photoluminescent self-healing elastomers containing dynamically hindered urea bonds were developed in this study, demonstrating excellent tensile properties (560 %), high strength (4.25 MPa), and good self-healing capabilities (95.45 % healing efficiency). The elastomer also exhibits unique photoluminescent characteristics, with luminous intensity varying under significant deformations. Photoluminescent characteristics are still present in 3D printed elastomers. Moreover, the elastomers can be utilized for 3D printing complex structures and customized sensors, with the printed sensors capable of achieving segmented responses. Resistive sensors prepared from this material exhibit high sensitivity and good cyclic stability, and they are capable of detecting various human motions while providing additional sensory information through changes in luminescent intensity. This study offers new insights into the development of photoluminescent self-healing materials for multifunctional applications, including smart wearable devices, dynamic displays, and optical sensors. [ABSTRACT FROM AUTHOR]

Generally, carbon nanoparticles with a size of 10 nm (or less) are called carbon quantum dots (CQDs, C-dots or CD), which have created huge excitement due to their advantages in chemical inertness, high water solubility, excellent biocompatibility, resistance to photobleaching and various optical superiority. In this article, we describe the recent advancements in the area of CQDs; concentrating on their synthesis techniques, size control, surface modification approaches, optical properties, luminescent mechanism, and their applications in bioimaging, biosensing, drug delivery and catalysis.

Carbon quantum dots (CQDs), a new family of photoluminescent 0D NPs, have recently received a lot of attention. They have enormous future potential due to their unique properties, which include low toxicity, high conductivity, and biocompatibility and accordingly can be used as a feasible replacement for conventional materials deployed in various optoelectronic, biomedical, and energy applications. The most recent trends and advancements in the synthesizing and setup of photoluminescent CQDs using environmentally friendly methods are thoroughly discussed in this review. The eco-friendly synthetic processes are emphasized, with a focus on biomass-derived precursors. Modification possibilities for creating newer physicochemical properties among different CQDs are also presented, along with a brief conceptual overview. The extensive amount of writings on them found in the literature explains their exceptional competence in a variety of fields, making these nanomaterials promising alternatives for real-world applications. Furthermore, the benefits, drawbacks, and opportunities for CQDs are discussed, with an emphasis on their future prospects in this emerging research field. [ABSTRACT FROM AUTHOR]

Six samarium (III) complexes were synthesised by employing the β-ketocarboxylic acid as main ligand and five N-donor systems as ancillary ligands through the environmentally safe liquid-assisted grinding method. Various characterisation techniques were employed to determine the structure of the complexes i.e. NMR, IR, XRD and SEM. Photoluminescent studies were carried out in solid as well as in solution form. In solid and solution form emission spectra show maximum intensity peak at 604 and 602 nm, respectively, assigned to 4G5/2 → 6H7/2 transition which explains orange emission on UV excitation in complexes. CCT, CP, colorimetric parameters and quantum yield (relative and intrinsic) of the synthesized complexes were calculated. With the help of reflectance spectra, band gap and Urbach energy were determined. Lasing parameters were also calculated by employing FWHM values obtained from Gaussian fitting. Energy transfer study revealed the efficacious energy transfer from ligand to metal's emissive level. Further antimicrobial studies revealed higher activity in case of complexes in comparison to ligand. [ABSTRACT FROM AUTHOR]

Fluorescent liquid crystal polymers have attracted much attention because of the combination of fluorescence, liquid crystallinity and processability. In this study, we designed and synthesised two series of photoluminescent cholesteric liquid crystal polysiloxanes, which contained cholesterol mesogens and fluorescein methyl ester with different side chain lengths. The chemical structures and liquid crystal properties of the polymers were investigated by the usual methods. The photoluminescent property were characterised by fluorescence spectroscopy. At the same time, the effects of the lengths of the fluorescent group chains on the liquid crystal and fluorescence properties of the polymers were studied. The results showed that the synthesised polymers possessing very good fluorescent and liquid crystal properties, which may has certain practical value and application prospect. [ABSTRACT FROM AUTHOR]

The wide application of fiber-reinforced polymer composite (FRPC) materials has given rise to the problem of their durability and performance over time. These problems are largely associated with their environmental conditions and service procedures, including ultraviolet (UV) irradiation. Here, we propose the production of polyester-based composites with different contents of synthesized Y3Al5O12:Ce3+,Ga (YAG:Ce,Ga) particles to provide sensing abilities towards material degradation. In this regard, the composites were subjected to UV radiation exposure, and its influence on the morphological, mechanical, and optical properties of the materials was investigated. Our findings reveal the self-sensing capabilities of the developed FRPC. The results indicate the potential of the system for the development of highly effective coatings allowing to detect and monitor UV degradation in composite materials for demanding applications. [ABSTRACT FROM AUTHOR]

Nacre structure has aragonite polygonal tablets, tessellated to generate separate layers, and exhibits adjacent layers and tablets within a layer bonded by a biopolymer. Here, we report the development of a nacre‐like organic/inorganic hybrid nanocomposite coating consisting of epoxy tablets as well as rare‐earth‐activated aluminate and graphene oxide tablet/tablet interfaces. The lanthanide‐activated aluminate was prepared using a high temperature solid‐state approach followed by top‐down technology to provide the phosphor nanoparticles (PNPs). Graphene oxide nanosheets were prepared from graphite. The prepared epoxy/graphene/phosphor nanocomposites were applied onto mild steel. Covalent bonds were formed between epoxy polymer chains resin and the graphene oxide nanosheets. These interface interactions resulted in a tough surface, high tensile strength, and excellent durability. The use of phosphor in the nanoparticle form guaranteed that no agglomerations were produced throughout the hardening procedure by allowing better distribution of PNPs in the nacre‐like matrix. The generated nacre‐like substrates displayed reversible fluorescence. The excitation of the white coloured nacre‐like coats at 367 nm resulted in a green emission band at 518 nm as designated by the Commission Internationale de l'éclairage (CIE) Laboratory and photoluminescence spectra. Various analysis methods were utilized to inspect the surface structure and elemental composition of the nacre‐like coats. An improved hydrophobicity and mechanical characteristics were detected when increasing the phosphor concentration. Due to the astonishing characteristics of the prepared nacre‐like composite paint, both ceramics and metals can benefit from the current simple strategy. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile (PAN) was often used as a composite fiber matrix due to its good spinning characteristics. Herein, photoluminescent quantum dot-doped nanofibers with tunable diameters were successfully prepared using electrospinning by adding CdSe/CdS quantum dots (QDs) in PAN spinning solution. The morphology and structure of CdSe/CdS-PAN nanofibers were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR), and the mechanical and photoluminescent properties of CdSe/CdS-PAN nanofibers were investigated. Stable photoluminescent nanofibers were obtained owning to the improved stability of photoluminescent property of CdSe/CdS QDs in the PAN nanofiber. The stable photoluminescent CdSe/CdS-PAN nanofibers might be used for anti-fake labels, ultraviolet sensors, smart textiles and optoelectronic devices. [ABSTRACT FROM AUTHOR]

This study aims to synthesize a core-shell gelatin-based carbon quantum dot-molecularly imprinted polymer (MIP@g-CQD) via the precipitation free-radical polymerization process using methotrexate (MTX) as a model anticancer template. To investigate the efficiency of the prepared photoluminescent MIP@g-CQD as a pH-responsive nano-carrier, MTX was loaded into MIP@g-CQD by soaking in a drug solution and the release behavior of the loaded drug was evaluated in the necessary pH values (7.4, 5). The successful synthesis of materials was characterized using PL, TEM, FE-SEM, DLS, and FT-IR analyses. Interestingly, the created cavities in the core-shell nano-carriers can interact with the MTX molecules effectively, leading to an increase in the loading capacity. According to the obtained results from Langmuir adsorption isotherms, the imprinting factor was calculated (IF = 4.91). Also, the binding kinetics of MTX revealed the creation of particular recognition sites in the core-shell polymeric network. The MTX-loaded MIP@g-CQD displayed a low rate and limited release at the simulated physiological environment (pH 7.4, 37 °C), but it is increased at tumor tissue (pH 5, 41 °C) conditions, which can lead to long-term and sustained release of MTX in the desired target. This property of MIP@g-CQD could avoid the release of MTX in normal physiological conditions, decreasing the possible side effects of MTX drug. Owing to the existence of amide functional groups in the nano-carrier structure and its negatively charged nature, the MTT assay displayed desirable cytotoxicity against the breast cancer cell line (MCF-7) for the MTX-loaded nano-carrier. According to the obtained results, the prepared safe photoluminescent MIP@g-CQD with appropriate pH-responsivity has a high ability to be applied as an anticancer and bio -detection agent. [Display omitted] • Functionalized g-CQDs were synthesized with a simple method and used as photoluminescent core in MIP. • Synthesized photoluminescent core-shell MIP@g-CQD can be employed as an effective anti-cancer and bio-detection agent. • Prepared MIP@g-CQD had exceptional biocompatibility, and can control drug release at simulated tumor tissue conditions. • The bio-based MIP@g-CQD had pH-response drug release property. [ABSTRACT FROM AUTHOR]

The synthesis of luminescent self-healing materials together with outstanding comprehensive mechanical features is yet a significant challenge due to the contradictory relationship between the self-healing features and mechanical characteristics. In this work, a lanthanide-based photoluminescent elastomer exhibiting super toughness and fast self-healing behavior was prepared via first synthesizing a photoluminescent complex and then utilizing which as the effective functional cross-linkers. The complexes were synthesized with p -aminobenzoic acid and 1,10-Phenanthroline as ligands, Ln3+ as the central luminescent ions. The backbone of the polymers was obtained by the polymerization of tolylene-2,4-diisocyanate-terminated polypropylene glycol (PPG-NCO) and isophorone diamine (IPDA). The addition of the complex as a cross-linking agent increases the degree of cross-linking of the polymer chains, and endows the material with good mechanical properties. In addition, self-healing properties was achieved thanks to the dynamic synergistic effect of Ln3+-ligand bonding and inter-amide hydrogen bonding. Furthermore, by varying the molar ratio of Eu3+/Tb3+, multi-color emission which ranging from red to green, has been accomplished. We are confident that the method employed in this study offers a little inspiration on the preparation of toughened luminescent products with self-healing features, which have wide ranging of applications in flexible optical devices, advanced information encryption, and other fields. A photoluminescent elastomer with outstanding toughness as well as rapid self-healing behavior was produced by first synthesizing a photoluminescent complex and then utilizing which as the effective cross-linkers. The addition of the complex as a cross-linking agent increases the degree of cross-linking of the polymer chains, and endows the material with good mechanical properties. The photoluminescent materials are colorless and transparent, and exhibit excellent strength (6.83 MPa), high toughness (80.29 MJ m−3), ability to self-recover rapidly and puncture resistance. Furthermore, by adjusting the molar ratio of Eu3+/Tb3+, multi-color emission which ranging from red to green, has been accomplished. [Display omitted] • Lanthanide-based luminescent polymers with self-healing properties were obtained. • The prepared materials show high toughness of 80.29 MJ m−3. • Multi-color emissions were achieved by adjusting the molar ratio of Eu3+/Tb3+. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amino-functionalized MOF can rapidly and selectively detect 3-NT through fluorescence quenching phenomenon. • Fluorescence quenching mechanism was investigated by UV–vis spectra and theoretical calculations. • This MOF-based sensor can also be used for the detection of 3-NT in actual mice serum samples. Sensitive and rapid detection of biomarker is an important but challenging task for diagnosis, treatment and monitoring of diseases. Herein, this study reports an amino-functionalized MOF-based fluorescent sensor (FJU-40-NH 2), which is selectively and significantly quenched by 3-nitrotyrosine (3-NT), a key biomarker of kidney disease, featuring ultra-fast detection time (<15 s), high quenching efficiency, superior anti-interference capability and low detection limit (0.55 µM). More importantly, this fluorescent sensor is successfully employed for the determination of 3-NT in both healthy and acute kidney injury mice serums with recoveries of 96.3–103.3 %. The fluorescence quenching mechanism is attributed to the synergistic effect of the photoinduced electron transfer and internal filtration effect, as confirmed by UV–vis spectra and theoretical calculations. [ABSTRACT FROM AUTHOR]

The objective is to utilize zero wastage rice hull material which contains silica as a major component in amorphous form and is used as reinforcement material for various applications. Burning of rice hull (RH) under controlled condition after removal of metal ions leads to white silica of high purity. An inexpensive method for extraction of amorphous silica by thermochemical treatment (pyrolysis process) is performed. Pyrolyzed biomass at four different temperatures is observed for treated and untreated rice hull. Calcination of the rice hull at 600ºC in a muffle furnace turns it into white amorphous silica. In this research, HCl was used to retrieve silica from the rice hull. Extracted silica was characterized by X-ray diffraction analysis, which indicates that the silica is in amorphous form, and displayed a strong broad peak at 22.32º and 21.52˚ (2θ). The FTIR data revealed the existence of peaks at 4000 cm− 1& 400 cm− 1 showing the presence of siloxane and silanol groups. UV-Visible (absorption) band maxima was demonstrated at 367 nm, photoluminescent (emission) spectra displayed a short peak at 453 nm and a sharp intensity peak at 488 nm is comparable with amorphous nano-silica. Less amount of silica appeared at the inner surface of rice hull fiber revealed by SEM analysis. Other element traces were absent, high purity of amorphous silica is observed by EDS. [ABSTRACT FROM AUTHOR]

The unique optoelectronic properties of metal halide perovskite quantum dots (QDs) make them promising candidates for applications in light-emitting diodes (LEDs), scintillators, and other photonic devices. The automated micropipetting synthesis platform equipped with an optical reader enables the opportunity for high throughput synthesis and photoluminescent (PL) characterization of metal halide perovskite QDs for the first time. Here, we explore the compositional dependence of the PL behavior and stability of the combinatorial library of cesium lead halide (CsPbX3) perovskites QDs via the automated platform. To study the stability of synthesized QDs in the binary and ternary configurations, we study the time-dependent PL properties using previously developed machine learning analysis. To systematically explore the PL behavior in the ternary CsPbX3 QDs system, we introduce the Bayesian inference framework that allows the probabilistic fit of multiple models to the PL data and establishes both optimal model and model parameter robustly. Furthermore, these behaviors can be used as a control parameter for the navigation of the multidimensional compositional spaces in automated synthesis. This analysis shows the nonuniformity of the PL peak behavior in the ternary CsPbX3 QDs system. Further, the analysis confirms narrow size distribution and good quality of CsPbBr3 QDs alloyed with low concentrations of iodide and chloride. We note that Bayesian Inference fit parameters can be further used as a control signal for navigation of the chemical spaces in automated synthesis.

The tracking of nanomedicines in their concentration and location inside living systems has a pivotal effect on the understanding of the biological processes, early-stage diagnosis, and therapeutic monitoring of diseases. Nanoscale metal-organic frameworks (nano MOFs) possess high surface areas, definite structure, regulated optical properties, rich functionalized sites, and good biocompatibility that allow them to excel in a wide range of biomedical applications. Controllable syntheses and functionalization endow nano MOFs with better properties as imaging agents and sensing units for the diagnosis and treatment of diseases. This minireview summarizes the tunable synthesis strategies of nano MOFs with controllable size, shape, and regulated luminescent performance, and pinpoints their recent advanced applications as optical elements in bioimaging and biosensing. The current limitations and future development directions of nano MOF-contained materials in bioimaging and biosensing applications are also discussed, aiming to expand the biological applications of nano MOF-based nanomedicine and facilitate their production or clinical translation., (© 2024 Wiley‐VCH GmbH.)

Ionogel has recently emerged as a promising ionotronic material due to its good ionic conductivity and flexibility. However, low stretchability and significant hysteresis under long-term loading limit their mechanical stability and repeatability. Developing ultralow hysteresis ionogels with high stretchability is of great significance. Here, a simple and effective strategy is developed to fabricate highly stretchable and ultralow-hysteresis noncovalent cross-linked ionogels based on phase separation by 3D printing of 2-hydroxypropyl acrylate (HPA) in 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF 4 ). Ingeniously, the sea-island structure of the physically cross-linked network constructed by the smaller nanodomains and larger nanodomain clusters significantly minimizes the energy dissipation, endowing these ionogels with remarkable stretchability (>1000%), ultra-low hysteresis (as low as 0.2%), excellent temperature tolerance (-33-317 °C), extraordinary ionic conductivity (up to 1.7 mS cm -1 ), and outstanding durability (5000 cycles). Moreover, due to the formation of nanophase separation and cross-linking structure, the as-prepared ionogels exhibit unique thermochromic and multiple photoluminescent properties, which can synergistically be applied for anti-counterfeiting and encrypting. Importantly, flexible thermo-mechano-multimodal visual ionotronic sensors for strain and temperature sensing with highly stable and reproducible electrical response over 20 000 cycles are fabricated, showing synergistically optical and electrical output performances., (© 2024 Wiley‐VCH GmbH.)

ZrO2 and ZrO2:Sm3+ nanopowders are synthesized by means of polyol method, from [Zr(NO3)2.xH2O] and (SmCl3·6H2O) precursors dissolved in a diethylene glycol medium. X‐ray diffraction (XRD) results show polymorphic powders because monoclinic structure and tetragonal are exhibited. The crystal size is estimated by Scherrer formula; an averaged crystallite size of 9 nm is obtained. Surface morphology study, by means of SEM, evidences multiform particles, some with straight edges associated with monoclinic or tetragonal structure. The chemical composition microanalysis results indicate agreement with ideal stoichiometry for ZrO2 and ZrO2:Sm3+ powders. The photoluminescence emission spectra show that maximum intensity is reached at λ = 614 nm due to transition 4G5/2→6H7/2, exciting with λex = 240 nm, which corresponds to sample ZrO2:Sm3+ (0.75 at%); this sample is labeled as M3. Very similar results are obtained by cathodoluminescence studies. On the contrary, exciting with λex = 380 nm (monitoring emission band peaked at 614 nm), emission bands of host lattice and ZrO2:Sm3+ are favored simultaneously. The luminescent quenching phenomenon occurs when doping concentration (Sm3+ ions) is >=0.75 at%. The photoluminescent emission exhibits a reddish orange color, characteristic of Sm3+ ions, and yellowish‐orange for cathodoluminescence emission. [ABSTRACT FROM AUTHOR]

With the development of nanotechnology, fluorescent silicon nanomaterials have been synthesized and applied in various areas. Among them, silicon quantum dots (SiQDs) are a new class of zero-dimensional nanomaterials with outstanding optical properties, benign biocompatibility, and ultra-small size. In recent years, SiQDs have been gradually utilized for constructing high-performance fluorescent sensors for chemical or biological analytes. Herein, we focus on reviewing recent advances in SiQD-based fluorescent biosensors from a broad perspective and discussing possible future trends. First, the representative progress for synthesizing water-soluble SiQDs in the past decade is systematically summarized. Then, the latest achievement of the design and fabrication of SiQD-based fluorescent biosensors is introduced, with a particular focus on analyte-induced photoluminescence (fluorescence) changes, hybrids of SiQDs with other materials or molecules, and biological ligand-modification methods. Finally, the current challenges and prospects of this field are highlighted.