First-Row d6 Metal Complex Enables Photon Upconversion and Initiates Blue Light-Dependent Polymerization with Red Light
(2023) In Angewandte Chemie - International Edition 62(43).- Abstract
Photosensitizers for sensitized triplet-triplet annihilation upconversion (sTTA-UC) often rely on precious heavy metals, whereas coordination complexes based on abundant first-row transition metals are less common. This is mainly because long-lived triplet excited states are more difficult to obtain for 3d metals, particularly when the d-subshell is only partially filled. Here, we report the first example of sTTA-UC based on a 3d6 metal photosensitizer yielding an upconversion performance competitive with precious metal-based analogues. Using a newly developed Cr0 photosensitizer featuring equally good photophysical properties as an OsII benchmark complex in combination with an acetylene-decorated... (More)
Photosensitizers for sensitized triplet-triplet annihilation upconversion (sTTA-UC) often rely on precious heavy metals, whereas coordination complexes based on abundant first-row transition metals are less common. This is mainly because long-lived triplet excited states are more difficult to obtain for 3d metals, particularly when the d-subshell is only partially filled. Here, we report the first example of sTTA-UC based on a 3d6 metal photosensitizer yielding an upconversion performance competitive with precious metal-based analogues. Using a newly developed Cr0 photosensitizer featuring equally good photophysical properties as an OsII benchmark complex in combination with an acetylene-decorated anthracene annihilator, red-to-blue upconversion is achievable. The upconversion efficiency under optimized conditions is 1.8 %, and the excitation power density threshold to reach the strong annihilation limit is 5.9 W/cm2. These performance factors, along with high photostability, permit the initiation of acrylamide polymerization by red light, based on radiative energy transfer between delayed annihilator fluorescence and a blue light absorbing photo-initiator. Our study provides the proof-of-concept for photon upconversion with elusive first-row analogues of widely employed precious d6 metal photosensitizers, and for their application in photochemical reactions triggered by excitation wavelengths close to near-infrared.
(Less)
- author
- Wang, Cui ; Wegeberg, Christina LU and Wenger, Oliver S.
- organization
- publishing date
- 2023-10-23
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Chromium(0) Complex, Energy Transfer, Laser Spectroscopy, Polymerization, Sensitized Triplet-Triplet Annihilation Upconversion
- in
- Angewandte Chemie - International Edition
- volume
- 62
- issue
- 43
- article number
- e202311470
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- pmid:37681516
- scopus:85171371190
- ISSN
- 1433-7851
- DOI
- 10.1002/anie.202311470
- language
- English
- LU publication?
- yes
- id
- 675059fc-938b-4c0f-b58e-c0ec88f8c574
- date added to LUP
- 2023-12-22 10:35:12
- date last changed
- 2024-04-20 20:55:49
@article{675059fc-938b-4c0f-b58e-c0ec88f8c574,
abstract = {{<p>Photosensitizers for sensitized triplet-triplet annihilation upconversion (sTTA-UC) often rely on precious heavy metals, whereas coordination complexes based on abundant first-row transition metals are less common. This is mainly because long-lived triplet excited states are more difficult to obtain for 3d metals, particularly when the d-subshell is only partially filled. Here, we report the first example of sTTA-UC based on a 3d<sup>6</sup> metal photosensitizer yielding an upconversion performance competitive with precious metal-based analogues. Using a newly developed Cr<sup>0</sup> photosensitizer featuring equally good photophysical properties as an Os<sup>II</sup> benchmark complex in combination with an acetylene-decorated anthracene annihilator, red-to-blue upconversion is achievable. The upconversion efficiency under optimized conditions is 1.8 %, and the excitation power density threshold to reach the strong annihilation limit is 5.9 W/cm<sup>2</sup>. These performance factors, along with high photostability, permit the initiation of acrylamide polymerization by red light, based on radiative energy transfer between delayed annihilator fluorescence and a blue light absorbing photo-initiator. Our study provides the proof-of-concept for photon upconversion with elusive first-row analogues of widely employed precious d<sup>6</sup> metal photosensitizers, and for their application in photochemical reactions triggered by excitation wavelengths close to near-infrared.</p>}},
author = {{Wang, Cui and Wegeberg, Christina and Wenger, Oliver S.}},
issn = {{1433-7851}},
keywords = {{Chromium(0) Complex; Energy Transfer; Laser Spectroscopy; Polymerization; Sensitized Triplet-Triplet Annihilation Upconversion}},
language = {{eng}},
month = {{10}},
number = {{43}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Angewandte Chemie - International Edition}},
title = {{First-Row d<sup>6</sup> Metal Complex Enables Photon Upconversion and Initiates Blue Light-Dependent Polymerization with Red Light}},
url = {{http://dx.doi.org/10.1002/anie.202311470}},
doi = {{10.1002/anie.202311470}},
volume = {{62}},
year = {{2023}},
}