TY - JOUR
T1 - A redox asymmetric, cyclometalated ruthenium dimer: toward upconversion dyes in dye-sensitized TiO2 solar cells
AU - Wadman, S.H.
AU - van Leeuwen, Y.M.
AU - Havenith, R.W.A.
AU - van Klink, G.P.M.
AU - van Koten, G.
PY - 2010
Y1 - 2010
N2 - Wehave prepared the dinuclear rutheniumcomplexes [(R3-tpy)Ru(N
∧
C
∧
N-tpy)Ru(tpy)]3þ
(R=H
([5a]3þ
), CO2Me ([6a]3þ
), N
∧
C(H)
∧
N-tpy = 40-(3,5-dipyridylphenyl)-2,20:60,200-terpyridine, tpy =
2,20:60,200-terpyridine) and [(R3-tpy)Ru(N0∧
C
∧
N0-tpy)Ru(tpy)]3þ
(R = H ([5b]3þ
), CO2Me ([6b]3þ
),
N0∧
C(H)
∧
N0-tpy = 40-(3,5-di(4-tert-butylpyridyl)phenyl)-2,20:60,200-terpyridine) in a stepwise manner.
The directional nature of the bridging ligand, which is potentially cyclometalating on one side,
induces large redox asymmetry in the resulting dinuclear complexes. One-electron oxidation gives
rise to a strong metal-to-metal charge transfer transition from the [Ru(tpy2)]2þ
moiety to the cycloruthenated
group, centered at 1034 nm for [6b]4þ
. The localized nature of the oxidation processes, the
shape of the NIR band, and TD-DFT calculations allow assignment of these systems to localized
Robin-Day class II. Exclusive substitution of the terminal tpy ligand on the cyclometalated
ruthenium with acid moieties allows selective attachment of the dye to a semiconductor surface,
whereby a possible two-step upconversion path is created in dye-sensitized solar cells for the
utilization of low-energy photons.
AB - Wehave prepared the dinuclear rutheniumcomplexes [(R3-tpy)Ru(N
∧
C
∧
N-tpy)Ru(tpy)]3þ
(R=H
([5a]3þ
), CO2Me ([6a]3þ
), N
∧
C(H)
∧
N-tpy = 40-(3,5-dipyridylphenyl)-2,20:60,200-terpyridine, tpy =
2,20:60,200-terpyridine) and [(R3-tpy)Ru(N0∧
C
∧
N0-tpy)Ru(tpy)]3þ
(R = H ([5b]3þ
), CO2Me ([6b]3þ
),
N0∧
C(H)
∧
N0-tpy = 40-(3,5-di(4-tert-butylpyridyl)phenyl)-2,20:60,200-terpyridine) in a stepwise manner.
The directional nature of the bridging ligand, which is potentially cyclometalating on one side,
induces large redox asymmetry in the resulting dinuclear complexes. One-electron oxidation gives
rise to a strong metal-to-metal charge transfer transition from the [Ru(tpy2)]2þ
moiety to the cycloruthenated
group, centered at 1034 nm for [6b]4þ
. The localized nature of the oxidation processes, the
shape of the NIR band, and TD-DFT calculations allow assignment of these systems to localized
Robin-Day class II. Exclusive substitution of the terminal tpy ligand on the cyclometalated
ruthenium with acid moieties allows selective attachment of the dye to a semiconductor surface,
whereby a possible two-step upconversion path is created in dye-sensitized solar cells for the
utilization of low-energy photons.
U2 - 10.1021/om100865k
DO - 10.1021/om100865k
M3 - Article
SN - 0276-7333
VL - 29
SP - 5635
EP - 5645
JO - Organometallics
JF - Organometallics
IS - 21
ER -