Influence of Doping and Temperature on Solvatochromic Shifts in Optical Spectra of Carbon Dots
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F16%3A33159997" target="_blank" >RIV/61989592:15310/16:33159997 - isvavai.cz</a>
Result on the web
<a href="http://pubs.acs.org/doi/pdf/10.1021/acs.jpcc.5b12294" target="_blank" >http://pubs.acs.org/doi/pdf/10.1021/acs.jpcc.5b12294</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1021/acs.jpcc.5b12294" target="_blank" >10.1021/acs.jpcc.5b12294</a>
Alternative languages
Result language
angličtina
Original language name
Influence of Doping and Temperature on Solvatochromic Shifts in Optical Spectra of Carbon Dots
Original language description
Solvatochromic shifts in nitrogen-doped and nitrogen-sulfur-co-doped carbon dots are studied by analyzing absorption, photoluminescence excitation and photoluminescence emission spectra, and their emission lifetimes in two different solvents, protic water (H2O) and aprotic dimethyl sulfoxide (DMSO). We identify three emission bands belonging to the sp(2)-hybridized core, the edge, and the functional surface groups of carbon dots, as well as surface attached fluorophores that emit within the edge band energy range. Edge and surface bands show opposite solvatochromic shifts solely depending on the doping heteroatoms. We are able to reproduce emission shifts observed in DMSO by heating CDs in H2O from 7 to 87 degrees C, when the polarity and hydrogen-bonding strength of the solvent are reduced. Intrinsic edge band transitions are found to be strongly influenced by the solvent polarity, as charge transfer processes dominate. Surface band transitions are found to be influenced especially by hydrogen bonding between the carbon dots and the solvent. Together, these processes lead to characteristic, solvatochromic blue and red shifts of the emission bands. Furthermore, we observe strong emission quenching in the edge band but emission enhancement in the surface band of carbon dots in DMSO. This is attributed to quenched organic fluorophores that are formed during the carbon dot synthesis, leaving only intrinsic edge band emission while the radiative decay in the surface band is enhanced. As a result, the edge band of nitrogen-sulfur-co-doped carbon dots switches from an excitation-independent, fluorophore-like emission to an excitation-dependent emission associated with intrinsic edge states.
Czech name
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Czech description
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Classification
Type
J<sub>x</sub> - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)
CEP classification
CF - Physical chemistry and theoretical chemistry
OECD FORD branch
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Result continuities
Project
<a href="/en/project/LO1305" target="_blank" >LO1305: Development of the center of advanced technologies and materials</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2016
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of Physical Chemistry Part C: Nanomaterials and Interfaces
ISSN
1932-7447
e-ISSN
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Volume of the periodical
120
Issue of the periodical within the volume
19
Country of publishing house
US - UNITED STATES
Number of pages
14
Pages from-to
10591-10604
UT code for WoS article
000376417500052
EID of the result in the Scopus database
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