Abstract
The electrochemical reduction of the Mn(bpy)(CO) 3 X CO 2 reduction catalyst is thought to proceed by the initial reduction of Mn I to Mn 0 . We have covalently attached a naphthalenediimide radical anion (NDI •- ) chromophore to the 4-, 5-, or 6-position of the bpy via a phenyl bridge to produce Mn(NDI •- -bpy)(CO) 3 X, where X = Br, CH 3 CN, or DMF, and have used femtosecond and nanosecond transient IR spectroscopy to directly observe the intermediates produced by two electron-transfer reactions following selective photoexcitation of NDI •- to its lowest excited doublet state, 2∗ NDI •- . In complexes where NDI •- is attached at the 4- or 5-position of bipyridine, only the reaction Mn( 2∗ NDI •- -bpy)(CO) 3 X → Mn(NDI-bpy •- )(CO) 3 X is observed, whereas in the complex where NDI •- is attached to the 6-position of bipyridine, the reaction sequence Mn( 2∗ NDI •- -bpy)(CO) 3 X → Mn(NDI-bpy •- )(CO) 3 X → Mn 0 (NDI-bpy)(CO) 3 is observed. Moreover, in the complexes with an NDI •- bound to the 6-position of bipyridine, Mn 0 (NDI-bpy)(CO) 3 exhibits a lifetime that is ∼10 5 times longer than those in complexes with an NDI •- bound at the four- or five-position of the bipyridine.
| Original language | English |
|---|---|
| Pages (from-to) | 6416-6426 |
| Number of pages | 11 |
| Journal | Journal of Physical Chemistry C |
| Volume | 123 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - Mar 21 2019 |
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ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Energy(all)
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
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Direct Observation of the Photoreduction Products of Mn(NDI-bpy)(CO) 3 X CO 2 Reduction Catalysts Using Femtosecond Transient IR Spectroscopy . / Martinez, Jose F.; La Porte, Nathan T.; Young, Ryan M.; Sinopoli, Alessandro; Sohail, Muhammad; Wasielewski, Michael R.
In: Journal of Physical Chemistry C, Vol. 123, No. 11, 21.03.2019, p. 6416-6426.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Direct Observation of the Photoreduction Products of Mn(NDI-bpy)(CO) 3 X CO 2 Reduction Catalysts Using Femtosecond Transient IR Spectroscopy
AU - Martinez, Jose F.
AU - La Porte, Nathan T.
AU - Young, Ryan M.
AU - Sinopoli, Alessandro
AU - Sohail, Muhammad
AU - Wasielewski, Michael R
PY - 2019/3/21
Y1 - 2019/3/21
N2 - The electrochemical reduction of the Mn(bpy)(CO) 3 X CO 2 reduction catalyst is thought to proceed by the initial reduction of Mn I to Mn 0 . We have covalently attached a naphthalenediimide radical anion (NDI •- ) chromophore to the 4-, 5-, or 6-position of the bpy via a phenyl bridge to produce Mn(NDI •- -bpy)(CO) 3 X, where X = Br, CH 3 CN, or DMF, and have used femtosecond and nanosecond transient IR spectroscopy to directly observe the intermediates produced by two electron-transfer reactions following selective photoexcitation of NDI •- to its lowest excited doublet state, 2∗ NDI •- . In complexes where NDI •- is attached at the 4- or 5-position of bipyridine, only the reaction Mn( 2∗ NDI •- -bpy)(CO) 3 X → Mn(NDI-bpy •- )(CO) 3 X is observed, whereas in the complex where NDI •- is attached to the 6-position of bipyridine, the reaction sequence Mn( 2∗ NDI •- -bpy)(CO) 3 X → Mn(NDI-bpy •- )(CO) 3 X → Mn 0 (NDI-bpy)(CO) 3 is observed. Moreover, in the complexes with an NDI •- bound to the 6-position of bipyridine, Mn 0 (NDI-bpy)(CO) 3 exhibits a lifetime that is ∼10 5 times longer than those in complexes with an NDI •- bound at the four- or five-position of the bipyridine.
AB - The electrochemical reduction of the Mn(bpy)(CO) 3 X CO 2 reduction catalyst is thought to proceed by the initial reduction of Mn I to Mn 0 . We have covalently attached a naphthalenediimide radical anion (NDI •- ) chromophore to the 4-, 5-, or 6-position of the bpy via a phenyl bridge to produce Mn(NDI •- -bpy)(CO) 3 X, where X = Br, CH 3 CN, or DMF, and have used femtosecond and nanosecond transient IR spectroscopy to directly observe the intermediates produced by two electron-transfer reactions following selective photoexcitation of NDI •- to its lowest excited doublet state, 2∗ NDI •- . In complexes where NDI •- is attached at the 4- or 5-position of bipyridine, only the reaction Mn( 2∗ NDI •- -bpy)(CO) 3 X → Mn(NDI-bpy •- )(CO) 3 X is observed, whereas in the complex where NDI •- is attached to the 6-position of bipyridine, the reaction sequence Mn( 2∗ NDI •- -bpy)(CO) 3 X → Mn(NDI-bpy •- )(CO) 3 X → Mn 0 (NDI-bpy)(CO) 3 is observed. Moreover, in the complexes with an NDI •- bound to the 6-position of bipyridine, Mn 0 (NDI-bpy)(CO) 3 exhibits a lifetime that is ∼10 5 times longer than those in complexes with an NDI •- bound at the four- or five-position of the bipyridine.
UR - http://www.scopus.com/inward/record.url?scp=85063324133&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85063324133&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.9b00138
DO - 10.1021/acs.jpcc.9b00138
M3 - Article
AN - SCOPUS:85063324133
VL - 123
SP - 6416
EP - 6426
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 11
ER -