The present work is an attempt to investigate the heavy atom effect imparted by halide ions, especially iodide (I) ions on the fluorescence behavior of carbon dots (CDs). Here two different types of CDs viz. nitrogen doped carbon dots (NCDs) from Citric Acid (CA) & Urea and Sulfur and nitrogen co-doped carbon dots (S,N-CDs) from CA & L-Cysteine were synthesized and the fluorescence of both CDs were quenched by heavy atom effect on adding potassium iodide (KI). The large difference in average lifetime was obtained in time-correlated single-photon counting (TCSPC) analysis suggests the dynamic quenching and heavy atom effect. Graphical abstract.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s10895-020-02607-x | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Singlets-Driven Photoredox Catalysts: Transforming Noncatalytic Red Fluorophores to Efficient Catalysts.
JACS Au
December 2024
Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060, United States.
Red-light absorbing photoredox catalysts offer potential advantages for large-scale reactions, expanding the range of usable substrates and facilitating bio-orthogonal applications. While many red-light absorbing/emitting fluorophores have been developed recently, functional red-light absorbing photoredox catalysts are scarce. Many photoredox catalysts rely on long-lived triplet excited states (triplets), which can efficiently engage in single electron transfer (SET) reactions with substrates.
View Article and Find Full Text PDFScaffolding and Heavy-Atom Effects of Metal Chains Enhanced Tunable Long Persistent Luminescence in Metal-Organic Frameworks.
Inorg Chem
December 2024
Key Laboratory of Chemical Additives for China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
Metal-organic frameworks (MOFs) with long persistent luminescence (LPL) have attracted extensive research attention due to their potential applications in information encryption, anticounterfeiting technology, and security logic. The strategic combinations of organic phosphor linkers and metal ions lead to tremendous frameworks, which could unveil many undiscovered properties of organics. Here, the synthesis and characterization of a three-dimensional MOF (Cd-MOF) is reported, which demonstrates enhanced blue photoluminescence and a phosphorescent lifetime of 124 ms as compared to the pristine linker (HL) under ambient conditions due to the scaffolding and heavy-atom effects of metal chains in the framework.
View Article and Find Full Text PDFHeavy atom effects on synthetic pyranoanthocyanin analogues.
Photochem Photobiol
December 2024
Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil.
Pyranoflavylium cations are synthetic analogues of pyranoanthocyanins, the much more color-stable compounds that are formed spontaneously from grape anthocyanins during the maturation of red wines. In the present work, our studies of the photophysical properties of pyranoanthocyanin analogues are extended to include nine pyranoflavylium cations substituted with one or two bromo and/or iodo heavy atoms. The room temperature fluorescence, 77 K fluorescence and phosphorescence, triplet formation in solution, and sensitized singlet oxygen formation, with excited state acidity suppressed by the addition of trifluoroacetic acid, are compared to those of similar pyranoflavylium cations that do not contain a heavy atom.
View Article and Find Full Text PDFCryogenic Rearrangements of Spiroheptadiyl: Light- or Heavy-Atom Quantum Tunneling?
J Phys Chem Lett
December 2024
Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 841051, Israel.
Triplet 1,4-spiro[2.4]heptadiyl () has been shown experimentally to undergo rapid ring-opening and subsequent 1,2-hydrogen shift upon generation via photolysis of a diazene precursor at cryogenic temperatures. Modern computational tools elucidate the potential energy surface and kinetics behind this cascade reaction, disproving the earlier hypothesized mechanism invoking hot molecule effects in the first ring-opening step and tunneling in the second hydrogen transfer step.
View Article and Find Full Text PDFNaphthalene Hydrodearomatization via Controllable Photocatalytic Hydroboration.
J Org Chem
December 2024
College of New Energy, State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, P. R. China.
The photocatalytic dearomative 1,4-hydroboration of naphthalenes with an N-heterocyclic carbene borane (NHC-BH) complex was reported herein with controllable regioselectivity and chemoselectivity. This protocol yielded a wide range of naphthalene derivatives bearing various functional groups, notably bioactive compounds. Hydroboration occurred through the cooperation of photoredox and hydrogen atom transfer via boryl radical addition to naphthalene and further selective protonation.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!