A group of silica gel electrolytes with lanthanide luminescent hybrid materials were assembled and investigated. Photophysical studies showed that terbium and europium hybrids displayed characteristic green and red emissions within the electrolytes. The influence of different concentration of the lanthanide hybrids on the electrochemical behavior of a gelled electrolyte valve-regulated lead-acid battery were studied through cyclic voltammograms, electrochemical impedance spectroscopy, water holding experiments and mobility tests. The morphology and particle size were analyzed by scanning electron microscopy. The results proved that lanthanide (Tb3+/Eu3+) luminescent materials are effective additives which will significantly improve the electrochemical properties of lead-acid batteries.

•A Hybrid inorganic-organic chemical sensor has been designed.•A stepwise assembly method has been used to generate responses.•Three targets could be determined by this functional sensor.The example of a lanthanide based hybrid nanoprobe has been developed through functionalization of carbon dots with the organic pendant arms (ethylenediaminetetraaceticdianhydride). This assay has been designed for the highly specific recognition of an anthracis biomarker (2,6-pyridinedicarboxylic acid, DPA) in pure aqueous medium and the improved red emissions increase with the addition of DPA. In the next stage, this nanosystem demonstrates high selectivity for the determination of copper ions in terms of the switch-off effect. Furthermore, the presence of thiols such as glutathione (GSH) has induced large enhancements of the red luminescence. The corresponding detection limits are determined to be 137 nM for DPA, 80 nM for Cu(II) and 50 nM for GSH respectively. The employments of organic solvents, separation treatments and advanced instrumentations have been ruled out during the detection processes. The luminescence changes can be realized with the bare eye observation under the irradiation of a portable UV lamp. The results reported here may open the new way for designing multiple tailor-made sensing systems by finely tuning the features of both organic moieties and carbon nanostructures.

•Self-sacrificing template with ultrasonic assisted synthesis was used.•Yttrium systems exhibited more intense emissions than gadolinium.•Lanthanide molybdates were achieved in the presence of polyaspartic acid.Reactions under hydrothermal conditions between lanthanide ions and different loading hosts (phosphates, vanadates and molybdates) lead to a group of rare earth-based solid state materials. As for the cases of phosphates and vanadates, a novel self-sacrificing template route with ultrasonic assisted hydrothermal treatments has been utilized. The emission intensities of building blocks derived from yttrium (YPO4:Eu3+ and YVO4:Eu3+) were significantly stronger than their counterparts (GdPO4:Eu3+ and GdVO4:Eu3+). Ultrasonic irradiation of reaction solution ahead of hydrothermal treatments would also improve their red luminescence. In the case of molybdates, red/green emissive phosphors (BaMoO4: Eu3+ and BaMoO4: Tb3+) were achieved in the presence of polyaspartic acid as the template. Their structures and photophysical features have been investigated in detail.

Sensors bearing functional units that could transform the chemical recognition into readable signals due to binding to single or even more targets have received much attention. Here, two F−/Cu2+ optical sensors based on lanthanide edifices were designed. The f–f forbidden transitions of lanthanide elements differ significantly from organic compounds since they exhibited favorable features such as narrow emissions and high color purity. Europium(III) complex of 2-(3-carboxyphenyl)imidazo[4,5-f]-1,10-phenanthroline (Eu-1) and europium(III) ternary complex of 2-(3-carboxyphenyl)imidazo[4,5-f]-1,10-phenanthroline and dibenzoylmethane (Eu-2) showed on–off changes in responses to the guest species. The excitation wavelength of Eu-2 could be extended to nearly visible light range, and this longer wavelength sensitisation will be useful in the selection of cheap laser sources. Generally organic complexes suffered from the instabilities in practical uses, the encapsulation of indicators into hosts will be necessary. Therefore, the lanthanide containing hybrid films which were composed of cross-linked siloxane and polymeric matrices were also prepared. The inorganic–organic film could be excited at 410 nm and demonstrated improved thermal stability. Moreover, we could detect F− and Cu2+ in aqueous mixed solution and this feature would be favorable for future uses.

Sol–gel-derived nanosilica materials covalently anchored by functionalized terbium complexes with different dimensions were prepared. Zero-dimensional hybrid had a diameter of 50 nm with regular spherical shape. The lengths and widths of 1D nanorod hybrid were in the range of 50–70 and 20–30 nm. The specific surface areas of the two-dimensional materials were 81 and 108 cm2/g, respectively. Both materials bind hemoglobin in aqueous buffer solution (pH 7.4) as shown by striking luminescence changes. These novel findings will pave the way for the application of novel nanostructured lanthanide hybrids in sensor devices.

•A novel organic–inorganic hybrid material was assembled.•It exhibits green emissions and recognizes fluoride in water.•Boron–fluoride interaction plays an important role in the sensing process.A novel luminescent organic-inorganic hybrid terbium material containing a boronic acid receptor site has been designed and synthesized. Ultra-violet excitation of the material results in green emission from the terbium core. Homogenous spherical nanoparticles with the average diameter of 60 nm were achieved by embedding the terbium complex onto a silica surface. The boron–fluoride interactions of the new material in an aqueous environment provide for a new on-off luminescence sensor for fluoride ions in the field of lanthanide based multifunctional materials.

•The pH probe offers a very wide working range in water (pH 1–14).•The emission changes have multiple colors.•Long-lived excited state lifetimes of Eu(III) has been used.•Two types of pH sensitive hydrogels were fabricated.A new type of Eu(III) ofloxacin complex as the fluorescent pH indicator has been presented. Compared to pure ligand, the complex offers more distinguished color changes (green–red–blue) derived from both lanthanide line emissions and the secondary ionization steps of ofloxacin. During the concentration dependence experiments, the photoluminescence studies on the complex showed that the excitation of this pH probe can occur at a very long wavelength which extends to visible range (Ex = 427 nm). Furthermore, the functional complex was successfully incorporated into soft networks and two novel luminescent hydrogels (rod and film) were fabricated. The soft materials also exhibited specific responses towards the pH variation. Finally, the onion cell-stain experiments were carried out to further confirm the validity of pH dependence and the results support the idea that the material will be suitable for monitoring biological samples in the future.A new type of Eu(III) ofloxacin complex as the fluorescent pH indicator has been reported. Compared to pure ligand, the complex offers more distinguished color changes (green–red–blue) derived from both lanthanide line emissions and the secondary ionization steps of ofloxacin.

•2-(Furanyl) imidazo [4,5-f]-1,10-phenanthroline can effecteively coordinate to Tb and Eu ions.•Its lanthanide complexes exhibited emission changes to fluoride ions.•More interestingly, the enhanced luminescence by acetate is high enough to be detected by naked eye.Modification of 1,10-phenanthroline moiety has obtained hydrogen-bond donor such as 2-(furanyl) imidazo [4,5-f]-1,10-phenanthroline and its lanthanide complexes exhibited red or green luminescence. Spectroscopic studies of UV–vis, Fluorescence and NMR present that the sensors give distinguished emission changes to fluoride ions. More interestingly, the acetate anion induced enhanced luminescence is high enough to be detected by naked eye.

ZnSnO3:Eu3+ and Sr1−xCaxMoO4:Tb3+ nanocrystals with controlled shape have been assembled in the presence of two driving forces (supersonic microwave co-assistance, abbreviated as SMC) simultaneously in less than 60 min at very low temperature (80 °C). Scanning Electronic Microscope (SEM) images further supported the existence of cubic crystals and shuttle-like structures. More interestingly, Eu(III) ion has been encapsulated into zinc stannate for the first time and ZnSnO3:Eu3+ can exhibit red emissions excited by long wavelength (395 nm). Similarly, it was found that Sr1−xCaxMoO4:Tb3+ had striking green luminescence. The parameters to improve the optical properties have been studied in detail. This convenient approach may be applicable to construct other phosphors with well-defined crystalline structures.Highlights► Supersonic microwave co-assistance method was used to prepare phosphors. ► The samples can exhibit green or red emissions. ► The morphology could be controllable.

A systematic study of the preparation of lanthanide (Eu3+, Tb3+, Sm3+ and Dy3+) phosphors was carried out and luminescent materials (red, green, orange-red and blue-yellow) were successfully achieved at low temperature (70 °C) in 45 min, using simultaneous supersonic and microwave irradiation. Scanning and transmission electron microscopic images indicate that one-dimensional nanorods with diameters of 10–20 nm and lengths of up to 200 nm were formed. The phosphors were entrapped in cellulose gels and the corresponding hydrogels were also strongly emissive.

Europium activated lanthanum phosphate were in situ formed within polymeric hydrogels as templates (polyacrylamide and polyacrylic acid) and the resulting sintered phosphors were obtained. Luminescence properties of cross-linked gels with LaPO4:Eu3+ were investigated by fluorescence and the results show the emission increased from 25 °C to 85 °C. Calcinated sample could exhibit distinguished 5D0 → 7F1 transition with orange-red color, which indicated Eu3+ ions occupy in the crystal lattice with inversion symmetry. More importantly, the products fabricated by hydrogel assembly show higher emission intensities compared with convention method.Highlights► Poly-electrolytes were used as templates to prepare solid state materials. ► LaPO4:Eu3+ fabricated by gels exhibited red emissions. ► Hydrogel assembly triggered higher emissions compared with convention method.