- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
One-step synthesis of hexylresorcinol calix[4]arene-capped ZnO–Ag nanocomposites for enhanced degradation of organic pollutants
摘要： In this study, hexylresorcinol calix[4]arene (HRCA) is introduced into the reaction system, and HRCA-capped ZnO–Ag nanocomposites are prepared via a simple one-step reflux method. HRCA is used not only as a reducing agent for deoxidizing Ag+ to Ag, but also as a protectant for wrapping around the microstructure of the formed ZnO–Ag. The prepared samples are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and water contact angle. The Ag nanoparticles and ZnO adhere to each other and HRCA molecules encapsulate on the surface of ZnO–Ag nanocomposites. HRCA-capped ZnO–Ag nanocomposites with different Ag contents are investigated for use in photodegradation of organic pollutants (rhodamine B (RhB) and levofloxacin hydrochloride). The sample with 10.20 mol% Ag, denoted as ZA3, exhibits the highest catalytic activity for photodegradation of RhB and levofloxacin hydrochloride. Moreover, ZA3 exhibits high stability during photodegradation of organic pollutants even after multiple reuses. The possible photocatalytic mechanism is discussed. We believe that ?O2– and h+ are the chief active species responsible for the photocatalytic activity of HRCA-capped ZnO–Ag nanocomposite system. HRCA-capped ZnO–Ag nanocomposite is expected to be an effective photocatalyst with potential application to sewage treatment under sunlight.
关键词： HRCA-capped ZnO–Ag,Photocatalysis,Resorcinol calix[4]arene,Ag seed
更新于2025-11-21 11:03:13
-
Modification of the electronic properties of the π-spacer of chromophores linked to calix[4]arene platform for DSSCs applications
摘要： We have developed two novel dyes based on p-tert-butyl-calix[4]arene in order to evaluate their behavior as sensitizer in photovoltaic devices. These dyes consist in a difunctionalized calix[4]arene with triphenylamine (TPA)-donor, a heteroaromatic π-conjugated spacer, thiophene and benzothiadiazole-phenyl ring, respectively and cyanoacetic acid as acceptor group. The effect of the p -spacer has been studied by UV-vis spectroscopy and Differential Pulse Voltammetry and the models compounds have been theoretically investigated. The dye bearing phenylbenzothiadiazole results in a bathochromic shifted absorption and an adequate efficiency to transfer charge from D to A. The considerable increase of the photocurrent density results in a better efficiency of the devices prepared with these novel dyes with respect to the p-tert-butyl-calix[4]arene derivatives bearing TPA dye. In particular, p-tert-butyl-calix[4]arene derivative based on phenylbenzothiadiazole has reached an efficiency value of 5.84 % which means an increase of 33 % of the efficiency over those calix[4]arene derivatives with TPA dye.
关键词： aggregation,calix[4]arene,multichromophore,benzothiadiazole,metal-free sensitizer
更新于2025-09-23 15:23:52
-
Fabrication of a Tyrosine Responsive Liquid Quantum dots based Biosensor Through Host-Guest Chemistry
摘要： Design and fabrication of a smart liquid quantum dots (LQDs) with high biomolecules selectivity and specificity remains a challenge. Herein, a multifunctional calix[4]arene derivatives (PCAD) was rationally designed and applied to fabricate a Tyr-responsive CdSe-LQDs system through host-guest chemistry. Such this biosensor displays an outstanding fluorescence/macroscopic response for Tyr and reversible fluidic features due to the hydrogen interaction between the PCAD of CdSe-LQDs and Tyr. These excellent results highlighted CdSe-LQDs as a promising platform for biological molecules recognition and separation in the future.
关键词： Calix[4]arene,Liquid Quantum dots,Biosensor,Host-Guest Chemistry,Tyrosine detection
更新于2025-09-11 14:15:04
-
New fluorescent sensor based on a calix[4]arene bearing two triazole–coumarin units for copper ions: application for Cu2+ detection in human blood serum
摘要： A novel fluorescent chemosensor calix[4]arene L, containing two fluorogenic coumarin units at the lower rim has been synthesized via click reaction. The structure of this chemosensor, was characterized by IR, NMR spectra and elemental analysis. Ion-binding properties of L were investigated in acetonitrile with different metal ions and the recognition process was monitored by fluorescence, UV-Vis and 1H NMR spectral changes. In comparison with other metal ions, chemosensor L showed a specific selectivity toward copper ions. The Job plot analysis revealed that the binding between L with Cu2+ is in 1:1 stoichiometry. The association constant (Ka) for the complex L.Cu2+ was found to be 1.6 × 105 M?1. The limit of detection of the sensor L was determined to be 5.4 × 10?7 M. This sensitive and selective chemosensor was successfully applied for the detection of Cu2+ ions in human blood serum with 90–100% recovery.
关键词： Coumarin units,Blood serum,Calix[4]arene,Fluorescent sensor,Copper ion
更新于2025-09-10 09:29:36
-
Physicochemical and Ion-Sensing Properties of Benzofurazan-Appended Calix[4]arene in Solution and on Gold Nanoparticles: Spectroscopy, Microscopy, and DFT Computations in Support of the Species of Recognition
摘要： A calix[4]arene conjugate (L) functionalized at the lower rim with a benzofurazan fluorophore (NBD) and at the upper rim with a thioether moiety has been synthesized and characterized by 1H NMR, 13C NMR, and mass spectrometry techniques. Both the absorption and emission spectral data for L in different solvents exhibited progressive changes with an increase in polarity. Ion recognition studies were performed by absorption and fluorescence spectroscopy using 10 different metal ions. Among these, Hg2+ exhibited greater changes in these spectra, whereas Cu2+ showed only significant changes and all other ions showed no change in the spectral features. Although the Hg2+ has dominant influence on the spectral features and provides a detection limit of 56.0 ± 0.6 ppb, the selectivity was hampered because of the presence of the derivatizations present on both the rims of L for ion interaction in solution. Therefore, L was immobilized onto gold nanoparticles (AuNPL) so that the upper rim derivatizations anchor onto the gold surface through Au?S interactions, and this leaves out only the lower rim NBD derivatization for interaction with ions selectively. The AuNPL’s were characterized by transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy (XPS) analyses. The surface characteristics were analyzed by contact angle measurements. The AuNPL’s exhibit greater selectivity and enhanced sensitivity for Hg2+ ions with a lowest detection limit of 48.0 ± 0.8 ppb. The immobilization of L onto AuNPs was reflected in the corresponding fluorescence lifetime values, and the addition of Hg2+ to either L or AuNPL showed fluorescence quenching. The reversible recognition of Hg2+ by L was demonstrated by titrating L or AuNPL with Hg2+ followed by tetra-butyl ammonium iodide for several cycles. The structural features of Hg2+-bound species were demonstrated by density functional theory computations and were supported by the XPS data. The Hg2+ induces aggregated fibrillar morphology into supramolecular L, as demonstrated by microscopy when Hg2+ was added either to L or to AuNPL, supporting aggregation-caused quenching.
关键词： calix[4]arene,benzofurazan,Hg2+ detection,DFT computations,fluorescence quenching,gold nanoparticles
更新于2025-09-04 15:30:14
-
Novel luminescent paper based calix[4]arene chelation enhanced fluorescence- photoinduced electron transfer probe for Mn2+, Cr3+ and F-
摘要： A novel structurally simple calix[4]arene attached 1-aminoanthraquinone associated lower rim calix[4]arene conjugate was synthesized and has been used as turn on/off/on fluorescence probe for Mn2+, Cr3+ and F-. This chelation enhanced fluorescence - photoinduced electron transfer (CHEF-PET) based TAAC probe has been applied for its analytical application in real samples such as Mn2+ from blood serum, Cr3+ and F- from industrial effluent with 94 - 99 % recovery. The limit of detection of this sensor is found to be 11 nM for Mn2+, 4 nM for Cr3+ and 19 nM for F- with the concentration range of 0-120 nM. Further, we report an easy-to-use, low cost and disposable paper-based sensing device for rapid chemical screening of Mn2+, Cr3+ and F-. The device comprises fluorescent sensing probes embedded into a nitrocellulose matrix where the resonance energy transfer phenomenon seems to be the sensing mechanism. It opens up new opportunities for simple and fast screening in remote settings where sophisticated instrumentation is not always available. The MOPAC-2016 software package has been used to optimize the TAAC using PM7 well established method and calculates the HOMO-LUMO energy band gap for structure TAAC and TAAC with Mn2+, Cr3+ and F- ion based structures.
关键词： paper based analytical device,computational study,CHEF,PET,calix[4]arene
更新于2025-09-04 15:30:14