| Records |
| Author |
Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P. |
| Title |
Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion |
Type |
A1 Journal Article |
Year  |
2024 |
Publication |
Advanced Materials |
Abbreviated Journal |
Advanced Materials |
| Volume |
|
Issue |
|
Pages |
|
| Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
| Abstract |
A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
001206226700001 |
Publication Date |
2024-04-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
29.4 |
Times cited |
|
Open Access |
|
| Notes |
PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWOVlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWOVlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. |
Approved |
Most recent IF: 29.4; 2024 IF: 19.791 |
| Call Number |
EMAT @ emat @c:irua:205967 |
Serial |
9130 |
| Permanent link to this record |
| |
|
| |
| Author |
Chakraborty, J.; Chatterjee, A.; Molkens, K.; Nath, I.; Arenas Esteban, D.; Bourda, L.; Watson, G.; Liu, C.; Van Thourhout, D.; Bals, S.; Geiregat, P.; Van der Voort, P. |
| Title |
Decoding Excimer Formation in Covalent–Organic Frameworks Induced by Morphology and Ring Torsion |
Type |
A1 Journal Article |
| Year |
2024 |
Publication |
Advanced Materials |
Abbreviated Journal |
Advanced Materials |
| Volume |
|
Issue |
|
Pages |
|
| Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
| Abstract |
A thorough and quantitative understanding of the fate of excitons in covalent–organic frameworks (COFs) after photoexcitation is essential for their augmented optoelectronic and photocatalytic applications via precise structure tuning. The synthesis of a library of COFs having identical chemical backbone with impeded conjugation, but varied morphology and surface topography to study the effect of these physical properties on the photophysics of the materials is herein reported. The variation of crystallite size and surface topography substantified different aggregation pattern in the COFs, which leads to disparities in their photoexcitation and relaxation properties. Depending on aggregation, an inverse correlation between bulk luminescence decay time and exciton binding energy of the materials is perceived. Further transient absorption spectroscopic analysis confirms the presence of highly localized, immobile, Frenkel excitons (of diameter 0.3–0.5 nm) via an absence of annihilation at high density, most likely induced by structural torsion of the COF skeletons, which in turn preferentially relaxes via long‐lived (nanosecond to microsecond) excimer formation (in femtosecond scale) over direct emission. These insights underpin the importance of structural and topological design of COFs for their targeted use in photocatalysis. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
001206226700001 |
Publication Date |
2024-04-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
29.4 |
Times cited |
|
Open Access |
|
| Notes |
PVDV, JC, AC, and IN acknowledge the FWO-Vlaanderen for research grant G020521N and the research board of UGent (BOF) through a Concerted Research Action (GOA010-17). JC acknowledges UGent for BOF postdoctoral grant (2022.0032.01). AC acknowledges FWO- Vlaanderen for postdoctoral grant (12T7521N). KM, DVT and PG acknowledges FWO- Vlaanderen for research grant G0B2921N. SB and DAE acknowledge financial support from ERC Consolidator Grant Number 815128 REALNANO. CHL acknowledges China Scholarship Council doctoral grant (201908110280). PVDV acknowledges Hercules Project AUGE/17/07 for the UV VIS DRS spectrometer and UGent BASBOF BOF20/BAS/015 for the powder X-Ray Diffractometer. PG thanks UGent for support of the Core Facility NOLIMITS. |
Approved |
Most recent IF: 29.4; 2024 IF: 19.791 |
| Call Number |
EMAT @ emat @c:irua:205967 |
Serial |
9118 |
| Permanent link to this record |
| |
|
| |
| Author |
Justo, Y.; Goris, B.; Sundar Kamal, J.; Geiregat, P.; Bals, S.; Hens, Z. |
| Title |
Multiple dot-in-rod PbS/CdS heterostructures with high photoluminescence quantum yield in the near-infrared |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| Volume |
134 |
Issue |
12 |
Pages |
5484-5487 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Pb cations in PbS quantum rods made from CdS quantum rods by successive complete cationic exchange reactions are partially re-exchanged for Cd cations. Using STEM-HAADF, we show that this leads to the formation of unique multiple dot-in-rod PbS/CdS heteronanostructures, with a photoluminescence quantum yield of 4555%. We argue that the formation of multiple dot-in-rods is related to the initial polycrystallinity of the PbS quantum rods, where each PbS crystallite transforms in a separate PbS/CdS dot-in-dot. Effective mass modeling indicates that electronic coupling between the different PbS conduction band states is feasible for the multiple dot-in-rod geometries obtained, while the hole states remain largely uncoupled. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000302489500015 |
Publication Date |
2012-03-16 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
|
| ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.858 |
Times cited |
41 |
Open Access |
|
| Notes |
Fwo; Iap |
Approved |
Most recent IF: 13.858; 2012 IF: 10.677 |
| Call Number |
UA @ lucian @ c:irua:96957 |
Serial |
2226 |
| Permanent link to this record |
