Journal of the American Chemical Society
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which are typically <100 ps.2 The relatively slow ET may be
due to a combination of low wavefunction overlap between
the hole localized on Ru3+ and the electron delocalized in a
CdS NR, significantly different electronic couplings for the
HT and the ET pathways, and the very large driving force for
ET (~1.9 eV) placing the process in the Marcus inverted re-
gime. Further work is needed to elucidate the factors that
determine the HT and ET rates in this system.
We gratefully acknowledge funding support from the Renewable
1
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5
6
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and Sustainable Energy Institute (RASEI), NSF CAREER grant
no. CHE-1151151 (MBW and GD), and the King Family Fellow-
ship at CU and the A.P. Sloan Foundation (NHD and HWT).
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These results have significant implications for photochem-
ical water splitting. Under the conditions of our current ex-
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where each HT event that oxidizes Ru2+ is followed by an ET
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– 100 ns. The second step could be averted through introduc-
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ASSOCIATED CONTENT
Supporting Information
Experimental; construction of Fig 1d energy level diagram; PL of
CdS NRs with free ligands of 1; discussion of concentration-
dependent PL quenching; TA spectra of CdS with and without 1;
data in Fig 3a on a linear time axis; absorption spectra showing
Asc oxidation; concentration-dependent TA kinetics. This materi-
AUTHOR INFORMATION
Corresponding Author
Gordana.Dukovic@colorado.edu; Niels.Damrauer@colorado.edu
Author Contributions
‡These authors contributed equally.
Notes
The authors declare no competing financial interests.
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ACKNOWLEDGMENT
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