Novel selective and sensitive optical chemosensor based on phenylfluorone derivative for detection of Ge(IV) ion in aqueous solution

Ion-Induced Nanoarchitectonics for Anthraquinone Single Crystals with Enhanced Fluorescence Properties

Recently, bioinspired fluorescent materials have drawn ever-increasing attention due to their ecofriendliness and easy accessibility. Herein, we demonstrate that anthraquinone/metal ion coordination complexes can form well-defined crystals and possess obvious fluorescence enhancement properties. The fluorescence quantum yields of anthraquinone/metal ion assemblies are more than 2 orders of magnitude compared to those of anthraquinone assemblies. The electronic structures of the first excited singlet states of anthraquinone/metal ion molecules are obtained, and the mechanism of the fluorescence enhancement is elucidated. Such photoluminescent anthraquinone/metal ion crystals can be considered as efficient phosphors in fabricating light-emitting diodes. This work provides a simple route for the development of highly efficient natural fluorescent materials.

Organic Dyes in Dye-Sensitized Solar Cells Featuring Back Reflector

Dye-sensitized solar cells (DSSCs) were fabricated using a photoelectrode covered by a porous layer of titanium dioxide, platinum counter electrode, iodide/triiodide electrolyte and three different dyes: phenylfluorone (PF), pyrocatechol violet (PCV) and alizarin (AL). After the adsorption of the dyes on the mesoporous TiO2 layer, the measurement of absorption spectra of all the tested dyes revealed a significant broadening of the absorption range. The positions of highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LUMO) levels of dye molecules were determined, indicating that all three dyes are good candidates for light harvesters in DSSCs. The cells were tested under simulated solar light, and their working parameters were determined. The results showed that the implementation of the back reflector layer made of BaSO4 provided an improvement in the cell efficiency of up to 17.9% for phenylfluorone, 60% for pyrocatechol violet and 21.4% for alizarin dye.

Preparation and Properties of Cryogel Based on Poly(2-hydroxyethyl methacrylate- co-glycidyl methacrylate)

The immobilized metal affinity cryogels based on poly(2-hydroxyethyl methacrylate- co-glycidyl methacrylate) (p(HEMA-GMA)) containing hydroxy and epoxy groups were prepared by free-radical copolymerization under cryogenic condition and then functionalized with iminodiacetic acid and chelated Cu²⁺, Ca²⁺, and Fe³⁺ ions to the p(HEMA-GMA) cryogel. The structures of p(HEMA-GMA) and immobilized metal-affinity cryogels were analyzed by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy. SEM results showed that the prepared cryogels had interconnected pores with the size of 30-100 μm. The performance of water swelling into the cryogels was fitted in Fickian diffusion. The adsorption property of cryogels was influenced by the immobilized ionic type, temperature, and adsorbate. The adsorption capacity of immobilized Cu²⁺ cryogel (p(HEMA)-Cu²⁺ (0.5 M) cryogel) was the highest in comparison with that of Ca²⁺ and Fe³⁺ affinity cryogels under the same condition. The maximum adsorption capacity of p(HEMA)-Cu²⁺ (0.5 M) cryogel for porcine pancreatic lipase was 150.14 mg/g at a higher temperature of 35 °C, whereas for bovine serum albumin, the maximum adsorption capacity was 154.11 mg/g at a lower temperature of 25 °C. The research of thermodynamics and kinetics indicated that the mechanism of the protein adsorption process corresponded to the Langmuir model and pseudo-second-order model.