In this paper, Eu3+ beta-diketone Complexes with the two ligands 1-(2-naphthoyl)-3, 3, 3-trifluoroacetonate (TFNB) and 2'2-bipyridine (bpy) have been synthesized. Furthermore, we reported a systematical study of the co-fluorescence effect of Eu(TFNB)3bpy doped with inert rare earth ions (La3+, Gd3+ and Y3+) and luminescence ion Tb3+. The co-luminescence effect can be found by studying the luminescence spectra of the doped complexes, which means that the existence of the other rare earth ions (La3+, Y3+, Gd3+ and Tb3+) can enhance the luminescence intensity of the central Eu3+, which may be due to the intramolecular energy transfer between rare earth ions and Eu3+. The efficient intramolecular energy transfer in all the complexes mainly occurs between the ligand TFNB and the central Eu3+. Full characterization and detail studies of luminescence properties of all these synthesized materials were investigated in relation to co-fluorescence effect between the central Eu3+ and other inert ions. Further investigation into the luminescence properties of all the complexes show that the characteristic luminescence of the corresponding Eu3+ through the intramolecular energy transfers from the ligand to the central Eu3+. Meantime, the differences in luminescence intensity of the 5D0-->7F2 transition, in the 5D0 lifetimes and in the 5D0 luminescence quantum efficiency among all the synthesized materials confirm that the doped complex Eu(0.5)Tb(0.5)(TFNB)3bpy exhibits higher 5D0 luminescence quantum efficiency and longer lifetime than the pure Eu(TFNB)3bpy complex and other materials.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/s10895-008-0456-5 | DOI Listing |
Nat Commun
December 2024
Key Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, Shaanxi, China.
Coordination complexes are promising candidates for powerful electrocatalytic oxygen evolution reaction but challenges remain in favoring the kinetics behaviors through local coordination regulation. Herein, by refining the synergy of carboxylate anions and multiconjugated benzimidazole ligands, we tailor a series of well-defined and stable coordination complexes with three-dimensional supramolecular/coordinated structures. The coordinated water as potential open coordination sites can directly become intermediates, while the metal center easily achieves re-coordination with water molecules in the pores to resist lattice oxygen dissolution.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
December 2024
Department of Chemistry and Material Science, College of Science, Nanjing Forestry University, Nanjing 210037, People's Republic of China. Electronic address:
For the typical ESIPT process, the proton transfer process is often completed via the intramolecular hydrogen bond (IHB) with oxygen or nitrogen as proton donor or proton acceptor. In recent years, the ESIPT process for sulfur-containing hydrogen bonds has received more and more attention, but it has been rarely reported. We systematically studied the ESIPT processes and photophysical properties of 2-(benzothiophene-2-yl)-3-hydroxy-4H-chromen-4-one (BTOH), 2-(benzothiophene-2-yl)-3-mercapto-4H-chromen-4-one (BTSH) and 2-(benzothiophen-2-yl)-3-hydroxy-4H-chromene-4-thione (BTS) at the HISSbPBE/6-31+G(d,p) and TD-HISSbPBE/6-31+G(d,p) computational level.
View Article and Find Full Text PDFACS Cent Sci
December 2024
Department of Molecular Sciences and Nanosystems, Ca' Foscari University of Venice, Via Torino 155, 30172 Mestre, Italy.
Computational generation of cyclic peptide inhibitors using machine learning models requires large size training data sets often difficult to generate experimentally. Here we demonstrated that sequential combination of Random Forest Regression with the pseudolikelihood maximization Direct Coupling Analysis method and Monte Carlo simulation can effectively enhance the design pipeline of cyclic peptide inhibitors of a tumor-associated protease even for small experimental data sets. Further studies showed that such -evolved cyclic peptides are more potent than the best peptide inhibitors previously developed to this target.
View Article and Find Full Text PDFACS Appl Mater Interfaces
December 2024
Key Laboratory of Industrial Ecology and Environment Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, PR China.
Photocatalytic conversion of carbon dioxide (CO) to fuel provides an ideal pathway to achieving carbon neutrality. One significant hindrance in achieving the reduction of CO to higher energy density multicarbon products (C) was the difficulty in coupling C-C bonds efficiently. Copper (Cu) is considered the most suitable metal catalyst for C-C coupling to form C products in the CO reduction reaction (CORR), but it encounters challenges such as low product selectivity and slow catalytic efficiency.
View Article and Find Full Text PDFFood Chem
December 2024
College of Food Science, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing, Chongqing 400715, China; Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, Chongqing 400715, China. Electronic address:
The traditional gelatin extraction methods (acid-base) may hinder to their green applications due to mass energy consumption and pollution. Herein, we constructed a clean and sustainable gelatin extraction method, investigated the molecular mechanism of microwave treatment (0-360 min) and freeze-thaw on the gelatin extraction from the perspective of the crosslinking degree and hydrogen bonds. Microwave (0-60 min) can improve the hydrolysis degree (DH) and expose more enzyme cleavage sites of collagen by destroying the intramolecular and intermolecular covalent crosslinking.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!