Strong Visible-Light-Absorbing Cuprous Sensitizers for Dramatically Boosting Photocatalysis

Article abstract of DOI:10.1002/anie.202003251

Developing strong visible-light-absorbing (SVLA) earth-abundant photosensitizers (PSs) for significantly improving the utilization of solar energy is highly desirable, yet it remains a great challenge. Herein, we adopt a through-bond energy transfer (TBET) strategy by bridging boron dipyrromethene (Bodipy) and a Cu^I complex with an electronically conjugated bridge, resulting in the first SVLA Cu^I PSs (Cu-2 and Cu-3). Cu-3 has an extremely high molar extinction coefficient of 162 260 m^?1 cm^?1 at 518 nm, over 62 times higher than that of traditional Cu^I PS (Cu-1). The photooxidation activity of Cu-3 is much greater than that of Cu-1 and noble-metal PSs (Ru(bpy)₃²⁺ and Ir(ppy)₃⁺) for both energy- and electron-transfer reactions. Femto- and nanosecond transient absorption and theoretical investigations demonstrate that a “ping-pong” energy-transfer process in Cu-3 involving a forward singlet TBET from Bodipy to the Cu^I complex and a backward triplet-triplet energy transfer greatly contribute to the long-lived and Bodipy-localized triplet excited state.

Full text of DOI:10.1002/anie.202003251

A Journal of the Gesellschaft Deutscher Chemiker
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Accepted Article
Title: Strong Visible Light-Absorbing Cuprous Sensitizers for
Dramatically Boosting Photocatalysis
Authors: Zhi-Ming Zhang, Kai-Kai Chen, Song Guo, Heyuan Liu, Xiyou
Li, and Tong-Bu Lu
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Strong Visible Light-Absorbing Cuprous Sensitizers for
Dramatically Boosting Photocatalysis
Kai-Kai Chen,[a] Song Guo,*[a] Heyuan Liu,[b] Xiyou Li,[b] Zhi-Ming Zhang,*[a] and Tong-Bu Lu[a]
Abstract: Developing strong visible-light-absorbing (SVLA) earth-
abundant photosensitizers (PSs) for significantly improving the
utilization of solar energy is highly desirable, yet it remains a great
challenge. Herein, we adopt a through-bond energy transfer (TBET)
strategy by bridging boron dipyrromethene (Bodipy) and a Cu(I)
complex with an electronically conjugated bridge, resulting in the first
SVLA Cu(I) PSs (Cu-2 and Cu-3). Cu-3 possesses an extremely
high molar extinction coefficient of 162260 M-1cm-1 at 518 nm, over
62 times higher than that of traditional Cu(I) PS (Cu-1). Remarkably,
the photooxidation activity of Cu-3 is substantially greater than that
lived 3MLCT state (metal-to-ligand charge transfer, πM → πL*) up
to the µs range via efficient intersystem crossing (ISC),
highlighting their potential for photochemical reactions.[38-41]
However, these copper PSs usually present weak visible-light-
harvesting abilities (< 3000 M-1cm-1), leading to much poorer
catalytic activities relative to those of traditional noble-metal PSs,
+
such as Ru(bpy)32+(Ru-1) and Ir(ppy)3 (Ir-1) (ppy
= 2-
phenylpyridine).[38-42] Thus, rationally designing and synthesizing
highly active copper(I) PSs with strong visible-light-absorbing
(SVLA) ability and long excited state lifetimes is an urgent task
but it remains a great challenge.
2+
+
of Cu-1 and noble-metal PSs (Ru(bpy)3 and Ir(ppy)3 ) for both
energy- and electron-transfer reactions. Femto- and nanosecond
transient absorption and theoretical investigations demonstrate that
a “ping-pong” energy-transfer process in Cu-3 involving a forward
singlet TBET from Bodipy to the Cu(I) complex and a backward
triplet-triplet energy transfer greatly contributed to the long-lived and
Bodipy-localized triplet excited state.
Through-bond energy transfer (TBET) has been regarded as
an efficient strategy for intramolecular energy-transfer; it
requires an electronically conjugated bridge to link the donor and
acceptor in a noncoplanar manner (Scheme 1).[43-45] Remarkably,
the TBET process is not limited by spectral overlap, which plays
a key role in determining the efficiency of the fluorescence
resonance energy-transfer process (FRET).[1,44,45] As a result,
TBET can dramatically expand the possible molecular designs
with the potential for efficient intramolecular energy transfer.[46]
However, TBET has never been applied to enhance the visible-
light-harvesting ability of earth-abundant transition-metal PSs.
To achieve SVLA PSs with long-lived excited state via a TBET
process, the following key factors are essential: (i) a donor with
SVLA ability, (ii) an acceptor with efficient ISC ability, (iii) an
acceptor with a lower singlet-state energy level compared to that
of the donor and (iv) a noncoplanar electronically conjugated
bridge between the donor and acceptor (Scheme 1).
Introduction
Photosensitizers (PSs) have been widely used as light-
harvesting molecules in both natural and artificial photosynthetic
systems for efficient solar energy conversion.[1-3] In recent
decades, noble-metal complexes have been widely explored as
PSs owing to their fascinating photophysical and photochemical
properties.[4-9] In this field, Ru(II),[10-15] Ir(III),[16-19] and Pt(II),[20-23]
complexes with long-lived excited states have been widely used
for intermolecular energy or electron transfers to promote
In this work, for the first time, we adopted the TBET strategy
to rationally design and synthesize SVLA cuprous Phen
3
photocatalysis.[24-26] In this field, we have tried to introduce IL-
sensitizers by introducing
a SVLA boron dipyrromethene
type Ir and Ru-PSs with long-lived excited state into
photocatalytic systems for boosting H2 production.[18,25]
Unfortunately, their high cost and ultra-low content in Earth’s
crust make them unsuitable for meeting the requirements of
long-term and large-scale applications.[24,27,28] Therefore,
increasing attention has been paid to exploring earth-abundant
transition-metal PSs.[29-32] Of particular interest are iron and
copper due to their low costs and toxicities.[29,33-36] Iron
complexes, such as [Fe(bpy)3]2+ (bpy = 2,2’-bipyridine) and
relevant polypyridyl coordination compounds, have been
designed and synthesized; however, they are rarely used as
PSs as their ultrashort excited state lifetimes are in the
picosecond range.[29,37] Copper(I) complexes, such as copper(I)
bis-phenanthroline (Phen) complex, can give a relatively long-
(Bodipy) as an energy donor to a Cu(I) complex (Scheme 1).
The Bis-(2,9-diphenyl-1,10-Phen) copper(I) complex with
efficient ISC (ca. 100 %) ability (triplet state energy level of 1.82
eV), and a low singlet state energy level (ca. 2.10 eV) was used
as the ideal spin convertor and energy acceptor. The careful
coupling of Bodipy with Cu(I)-Phen results in two SVLA cuprous
PSs (Cu-2 and Cu-3). Furthermore, a “ping-pong” energy-
transfer process was first observed in these Cu(I) PSs (Cu-2
and Cu-3) with a forward singlet TBET from the Bodipy to the
Cu(I) complex and a backward triplet-triplet energy transfer
(TTET).[47] This process also contributes substantially to
achieving the long-lived excited-states for Cu-2 and Cu-3 (27.2
µs for Cu-3 and 33.8µs for Cu-2), which are approximately 100
and 125 times longer than that of Cu-1 (0.27 µs for Cu-1). As a
result, the superior SVLA ability, long-lived excited-state and
efficient intramolecular energy transfer of Cu-3 can facilitate
photocatalysis for both energy- and electron-transfer reactions.
Its performance for photooxidation of 1,5-dihydroxynaphthalene
(DHN) was significantly enhanced, ca. 69.2, 14.8 and 15.7 times
higher than those of Cu-1, and noble-metal PSs Ru-1 and Ir-1,
respectively.
[a] K. K. Chen, Dr. S. Guo, Prof. Z. M. Zhang, Prof. T. B. Lu.
MOE International Joint Laboratory of Materials Microstructure, Institute for
New Energy Materials and Low Carbon Technologies, School of Materials
Science & Engineering, Tianjin University of Technology, Tianjin 300384,
China
E-mail: guosong@email.tjut.edu.cn; zmzhang@email.tjut.edu.cn
[b] Dr. H. Y. Liu, Prof. X. Y. Li
College of Science, China University of Petroleum (East China), Qingdao,
Shandong 266580, China
Supporting information for this article is given via a link at the end of the
document.
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RESEARCH ARTICLE
Scheme 1. Through-bond energy transfer cassettes (up) and the assembly process (down) of Cu-1 - Cu-3 and the structure of L-1 and L-2.
almost completely quenched in Cu-2 and Cu-3 under the same
Results and Discussion
conditions, which indicates an efficient energy or electron
transfer from Bodipy to the Cu(I) coordination center.
Furthermore, the emission intensities of Cu-2 and Cu-3 at 700
nm obviously increase with the introduction of Bodipy upon
selective excitation of the Bodipy ligand, which preliminarily
confirmed the efficient energy transfer from Bodipy to the Cu(I)
center (Figure S25), demonstrating efficient TBET processes in
these two complexes. Furthermore, the emission of Cu-2,
phenyl-Bodipy (Ph-Bodipy), and the mixture of Cu-1/Ph-Bodipy
were compared with optically matched solutions at the same
absorbance (Figure S25). As shown in Figure S25, both Bodipy
and the mixed system show a strong emission peak with similar
emission intensity at around 539 nm, however, the emission of
Bodipy part in Cu-2 was almost quenched completely. This
result further confirmed that the excitation energy of the Bodipy
unit could be efficiently transferred to Cu(I) coordination center
in Cu-2. This conclusion was further supported by the well-
matched absorption and excitation spectra of Cu-2 and Cu-3
(Figure S26).
The details of the synthetic process are shown in Scheme 1
and scheme S1. In this process, Cu-1, Cu-2 and Cu-3 can be
facilely prepared by reactions of Cu(CH3CN)4PF6 with L-1, the
mixture of L-1 and L-2, and L-2, respectively. Both intermediates
(L-1 and L-2) and the Cu(I) complexes (Cu-1-Cu-3) were well
defined and characterized by NMR spectroscopy and mass
spectrometry (Figure S1-S21). Notably, a benzene ring was
used as the electronically conjugated bridge to link the Bodipy
and Cu(I) complex (for Cu-2 and Cu-3). The ground-state
structures of these Cu(I) PSs, optimized by DFT calculations,
show significant torsion between Bodipy and the Phen ligand
around the Cu(I) center, which would allow efficient TBET from
Bodipy to the Cu(I) complex (Figure S22).
In recent decades, much attention has been paid to exploring
visible-light-harvesting copper complexes to enhance the
utilization of solar energy.[48,49] Herein, Cu(I) PSs with SVLA
ability were first achieved with high molar extinction coefficients
of 79876 M-1cm-1 for Cu-2 and 162260 M-1cm-1 for Cu-3 at 518
nm, and these are 30.8 and 62.5-fold higher than that of Cu-1
(2595 M-1cm-1 at 443 nm), respectively (Figure 1, S23 and Table
S1-S2). To evaluate their intramolecular energy-transfer
efficiencies, the ground-state absorption and photoluminescence
spectra of Cu-1, Cu-2, Cu-3 and L-2 were compared in detail
(Figure 1a, 1b and S24). As shown in Figure 1b, L-2 exhibits a
strong fluorescence emission peak at 550 nm, and this peak is
Femtosecond transient absorption experiments were further
performed to track the TBET process of Cu-3 (Figure 1c). Upon
excitation at 510 nm, the bleaching peak at approximately 519
nm for L-2 went back to zero, and its recovery was fitted to 1.3
ns, which has the same order of magnitude as that of the Bodipy
chromophore, and this recovery can be attributed to the
depletion of its ground state (Figure S27-S28). For Cu-3, the
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decay of the bleaching peak at 519 nm was determined to be
33.6 ps, which is much faster than that of L-2. In addition, the
weak bleaching at approximately 472 nm emerged, which could
between 480 nm and 650 nm, which indicates that Cu-1 has a
typical 3MLCT excited state.[48] Both Cu-2 and Cu-3 exhibit a
bleaching peak at 518 nm, consistent with the ground-state
be attributed to the formation of a singlet state in the Cu(I) center. absorption of Bodipy, and two positive peaks at approximately
The TBET process thus provides a viable pathway for efficient
and fast singlet energy transfer, which will facilitate the use of all
the excitation energy.
To uncover the properties of the triplet excited states,
nanosecond time-resolved transient absorption spectra of Cu(I)
PSs were acquired (Figure 1d, 1e and S29). Upon pulsed laser
excitation at 532 nm, Cu-1 presents a bleaching band between
420 nm and 480 nm and a positive absorption band
445 and 680 nm, corresponding to the triplet state absorption of
Bodipy, indicating a Bodipy-localized triplet state for Cu-2 and
Cu-3. Notably, as the triplet state of Cu PSs switched from the
3
3MLCT to IL state, this process also contributes substantially to
achieve the long-lived excited states for Cu-2 and Cu-3 (27.2 µs
for Cu-3 and 33.8µs for Cu-2), which can efficiently promote
intermolecular energy
/
electron transfer for efficient
photocatalysis (Figure 1f and S29-S30).
Figure 1. a) Ground-state absorption of Cu-1–Cu-3, b) Photoluminescence spectra of L-2, Cu-2 and Cu-3 with an excitation
wavelength (ex) of 500 nm, c) Femtosecond transient absorption spectra show the map of Cu-3 and its decay (inset) at 519 nm,ex
=
532 nm. Nanosecond transient absorption spectra show the map of d) Cu-1, ex = 532 nm and e) Cu-3, ex = 532 nm, f) Comparison
of the molar extinction coefficients and triplet state lifetimes of Cu-1–Cu-3.
To in-depth understand the excited state properties and
intramolecular energy transfer process of these Cu(I) PSs,
Gaussian calculations were performed using the DFT and time-
dependent DFT (TDDFT) methods. The spin-density surfaces of
Cu(I) PSs were calculated to reveal their triplet state population.
As shown in (Figure 2), the triplet state of Cu-1 was localized on
the Cu-Phen coordination unit and that of Cu-2 and Cu-3 was
mainly populated on the Bodipy ligand, which matched well with
the results of transient absorption spectra (Figure 1 and S29).
In order to further unveil photophysical processes of Cu-3,
UV–vis absorption and triplet excited state were rationalized
based on optimized ground-state geometry by TDDFT method
(Figure 3, S31-S32 and Table S3-S5). Two main transitions of
the calculated UV−vis absorption were determined as S0→S7
and S0→S12, locating at 493 nm and 442 nm, respectively. In
view of the analysis of molecular orbitals, the transitions of
S0→S7 and S0→S12 were distributed on Cu(I) coordination center
and Bodipy ligands in Cu-3, and the corresponding oscillator
strengths (f) were estimated as 0.0062 and 1.4894, respectively.
These results indicate the poor visible light absorption ability for
Cu(I) center and SVLA ability for Bodipy ligands, which was well
consistent with the experimental absorption spectra (Figure 1a
and S23). Then the singlet excited state of Cu-3 was populated
via a vibrational relaxation (VR) process. The singlet excited
state of Cu center was lower than that of Bodipy ligand, which
was confirmed by emission spectra (Figure S24). Therefore, it’s
reasonable to transfer singlet excited state energy from Bodipy
ligand to Cu(I) center via a TBET process. Owing to the heavy
atom effect of Cu, an ISC process proceeded to afford the triplet
state (T7), which was localized at Cu(I) center.
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center and
a
backward TTET from Cu(I) center to
Bodipy.Ultimately, the triplet state of Cu-3 was populated on the
Bodipy part, which further initiated the electron transfer for
efficient redox reactions.
To assess the reliability of the theoretical results, Gaussian
calculations were further performed with M06 (Figure S31 and
S32, Table S4).[50] As a result, the theoretical results obtained
with M06 were similar to that obtained with B3LYP, confirming
that both the computational functions are reasonable in these
multicomponent Cu-based complexes(Table S5).[30]
These advantages, including the superior SVLA ability, long
excited lifetime and efficient intramolecular energy transfer, of
Cu-2 and Cu-3 indicate their great potential for boosting
photocatalysis. The sensitizing abilities of these earth-abundant
Cu(I) PSs (Cu-1 - Cu-3) were examined in the photooxidation of
DHN to juglone (Figure 4, S33-S39, and Table S2). Juglone, an
important moiety in drug molecules, irreversibly inhibits peptidyl-
prolyl cis/trans isomerases in the parvulin family.[19] As shown in
Fig. S33, upon excitation with a 175 W xenon lamp, the triplet
state of Cu-3 was populated via a series of intramolecular
photophysical processes. Then, O2 is sensitized into singlet
oxygen (1O2) through a TTET process between Cu-3 and O2,
which is highly dependent on the triplet lifetime of PSs. In the
photooxidation reaction, the intensity of the absorption peak at
Figure 2. Spin-density surface of Cu-1-Cu-3 at the triplet state,
calculated at B3LYP/6–31G /LanL2DZ level with Gaussian 09W.
In addition, the T1 and T2 states were mainly populated on two
Bodipy ligands, respectively, which were degenerate due to their
similar energy level (1.53 eV for T1 and 1.53 eV for T2). The
energy level of T1 and T2 was much lower than that of T7,
signifying that the triplet state energy transfer from Cu(I) center
to Bodipy is feasible to afford a Bodipy localized triplet state.
This result was in line with spin density surfaces and transient
301 nm of DHN gradually decreased, and
a new peak
spectrum of Cu-3 (Figure 1e and 2). As
a result, the
corresponding to the formation of juglone began to grow in at
427 nm.
intramolecular photophysical processes of Cu-3 were well
clarified, revealing a forward TBET process from Bodipy to Cu(I)
Figure 3. Selected frontier molecular orbitals involved in the excitation and triplet excited state of Cu-3. VR stands for vibrational
relaxation. The left column is UV–vis absorption (based on ground state geometry), the middle column is the fluorescence emission,
and the right column is the triplet excited state (based on ground state geometry). For clarity, only selected excited states are
presented.
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As shown in (Figure 4), the change in the absorption peaks of
DHN in the presence of Cu-3 was much faster than that with Cu-
1, indicating a much greater enhancement of the sensitizing
ability with Cu-3. For comparison, the sensitizing ability of Cu-2,
noble-metal PSs Ru-1 and Ir-1 and long triplet lifetime PS
tetraphenylporphyrin (TPP) were also studied under the same
conditions (Figure S34 and S35). Specifically, the conversion
rate (Kobs) of Cu-3 was as high as 5.2 × 10-2 min-1, 69.2 times
faster than that of Cu-1, and much higher than that of the noble-
metal (Ru-1, Ir-1) and benchmark PSs (TPP). The yield of
juglone with Cu-3 as PS can reach to over 80 % within 60 min,
representing the highest yield among the above PSs (Figure 4d).
In addition, singlet oxygen quantum yield of Cu-3 was
determined to be 0.85 with Rose Bengal as standard (0.80).
This value is higher than the benchmark PSs, such as Rose
Bengal (0.80) and TPP (0.62), indicating that Cu-3 is
the state-of-the-art PS for 1O2 generation. Notably, the
absorption spectra of Cu-1 - Cu-3 or DHN alone remained
constant throughout 1 h irradiation with a 175 W xenon lamp
(Figure S37). These results indicate that complexes Cu-1 - Cu-3
exhibit an excellent photostability in the presence of dioxygen
(Figure S37). Thus, these compounds are sufficiently stable
under the catalytic conditions and Cu-3 is indeed an efficient PS
for driving this energy-transfer reaction.
reaction of 4-formylphenyl boronic acid in the presence of Cu-3
can efficiently produce 4-formylphenol in 97% yield within 4 h,
and this yield is 4 times higher than that with Cu-1 (20%). A
trace amount of 4-formylphenol can be detected in the absence
of Cu PSs, DIPEA, O2 or light, indicating that all the above
components are essential for the efficient photocatalytic aerobic
oxidation of aromatic boronic acids (Figure 5a). Remarkably,
Cu-3 exhibits a broad substrate scope with over 80% yield for
different aromatic boronic acids and borates, and it significantly
outperformed the noble-metal PSs Ru-1 and Ir-1 (Figure 5b). As
a result, Cu-3 represents a state-of-the-art Cu(I) PSs for both
energy- and electron-transfer reactions.
Figure 5. a) Photocatalytic oxidative hydroxylation of arylboronic
acids to produce phenols. b) Yields of phenols obtained from
different arylboronic acids in the presence of Cu-1, Cu-3, Ru-1
and Ir-1 upon irradiation with a 525 nm LED (23 mW•cm-2). cPS
=
20.0 µM (0.12 mol% vs substrates). c) The “ping-pong” energy-
transfer process in Cu-3 for both energy- and electron-transfer
reactions.
Conclusion
In this work, a TBET strategy was first extended to construct
earth-abundant transition-metal PSs with SVLA ability and long
excited-state lifetimes. Bodipy was carefully integrated into a
Cu(I) complex to afford the first Cu-based PSs with SVLA
abilities (Cu-2 and Cu-3). Upon light irradiation, the SVLA
Bodipy in Cu-3 can harvest visible light to reach its singlet
excited state and then efficiently deliver excitation energy to the
Cu(I) coordination center via a TBET process. Then, an ISC
process produces the triplet excited state of the Cu(I) center,
which can further deliver energy to the Bodipy ligand by a back
TTET process (Figure 5c). These advantages, the SVLA ability,
long excited-state lifetime and efficient intramolecular energy
transfer, of Cu-2 and Cu-3 can synergistically enhance
photocatalysis. The catalytic performance of the earth-abundant
PS Cu-3 for both energy- and electron-transfer reactions
significantly outperforms the Cu-1 and noble-metal PSs Ru-1
and Ir-1. Especially for the photooxidation of DHN, the
conversion rate (Kobs) with Cu-3 was 69.2, 14.8 and 15.7 times
faster than those of Cu-1, Ru-1 and Ir-1, respectively. This work
Figure 4. UV-vis absorption spectral changes in the
photooxidation of DHN (0.15 mM) using a) Cu-1 and b) Cu-3 as
singlet O2 sensitizers, c) plot of ln(Ct/C0) against irradiation time
(t), and d) the yields of juglone during 1 h irradiation with
different PSs. cPS
= 10.0 µM (6.7 mol% vs DHN) in
CH2Cl2/MeOH (9/1, v/v). Irradiated with a 175 W Xe lamp (17
mW•cm2).
The photocatalytic aerobic oxidation of aromatic boronic acids
to produce phenols represents
a typical electron-transfer
reaction,[51] and it was employed here to evaluate the sensitizing
activity of these Cu-PSs (Figure 5 and S40-S41). As shown in
Figure S40, the excited PSs accepted an electron from N,N-
diisopropylethylamine (DIPEA) and then delivered the electron
to O2 to produce O2•-. The efficiency of this reaction was
determined by the visible-light-harvesting ability, excited-state
lifetime and redox potential of each PS (Figure S42 and Table
S6). Under ambient atmospheric conditions, the photocatalytic
provides
a
new strategy for developing earth-abundant
multicomponent arrays with SVLA ability and long-lived excited
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[34] C.E. McCusker, F.N. Castellano, Inorg. Chem. 2013, 52, 8114-8120.
[35] J.D. Braun, I.B. Lozada, C. Kolodziej, C. Burda, K.M.E. Newman, J. van
Lierop, R.L. Davis, D.E. Herbert, Nat. Chem. 2019, 11, 1144-1150.
[36] M.T. Miller, P.K. Gantzel, T.B. Karpishin, J. Am. Chem. Soc. 1999, 121,
4292-4293.
states to facilitate photocatalysis for enhancing the solar energy
utilization.
[37] S.M. Fatur, S.G. Shepard, R.F. Higgins, M.P. Shores, N.H. Damrauer, J.
Am. Chem. Soc. 2017, 139, 4493-4505.
[38] D.G. Cuttell, S.M. Kuang, P.E. Fanwick, D.R. McMillin, R.A. Walton, J.
Am. Chem. Soc. 2002, 124, 6-7.
Acknowledgements
[39] R.S. Khnayzer, C.E. McCusker, B.S. Olaiya, F.N. Castellano, J. Am.
Chem. Soc. 2013, 135, 14068-14070.
[40] M.W. Mara, D.N. Bowman, O. Buyukcakir, M.L. Shelby, K. Haldrup, J.
Huang, M.R. Harpham, A.B. Stickrath, X. Zhang, J.F. Stoddart, A.
Coskun, E. Jakubikova, L.X. Chen, J. Am. Chem. Soc. 2015, 137,
9670-9684.
[41] S.P. Luo, E. Mejia, A. Friedrich, A. Pazidis, H. Junge, A.E. Surkus, R.
Jackstell, S. Denurra, S. Gladiali, S. Lochbrunner, M. Beller, Angew.
Chem. Int. Ed. 2013, 52, 419-423.
This work was supported by National Key R&D Program of
China (2017YFA0700104) and the National Natural Science
Foundation of China (Nos. 21703155, 21722104, 21671032),
Natural Science Foundation of Tianjin City of China
(18JCQNJC76500, 18JCJQJC47700, 17JCQNJC05100).
[42] N. Armaroli, C. Boudon, D. Felder, J.-P. Gisselbrecht, M. Gross, G.
Marconi, J.-F. Nicoud, J.-F. Nierengarten, V. Vicinelli, Angew. Chem. Int.
Ed. 1999, 38, 3730-3733.
[43] S. Speiser, Chem. Rev. 1996, 96, 1953-1976.
[44] G.S. Jiao, L.H. Thoresen, K. Burgess, J. Am. Chem. Soc. 2003, 125,
14668-14669.
Keywords: Cu(I) photosensitizier • strong visible light absorption
• through-bond energy transfer • long-lived triplet state •
photocatalysis
[45] R. Bandichhor, A. D. Petrescu, A. Vespa, A. B. Kier, F. Schroeder, K.
Burgess, J. Am. Chem. Soc. 2006, 128, 10688-10689.
[46] J. Han, A. Loudet, R. Barhoumi, R.C. Burghardt, K. Burgess, J. Am.
Chem. Soc. 2009, 131, 1642-1643.
[47] U. Hahn, J.-F. Nierengarten, B. Delavaux-Nicot, F. Monti, C. Chiorboli,
N. Armaroli, New. J. Chem. 2011, 35, 2234.
[48] M. Ruthkosky, F.N. Castellano, G.J. Meyer, Inorg. Chem. 1996, 35,
6406-6412.
[49] S. Garakyaraghi, C.E. McCusker, S. Khan, P. Koutnik, A.T. Bui, F.N.
Castellano, Inorg. Chem. 2018, 57, 2296-2307.
[50] E. Leoni, J. Mohanraj, M. Holler, M. Mohankumar, I. Nierengarten, F.
Monti, A. Sournia-Saquet, B. Delavaux-Nicot, N. Jean-Franco Is, N.
Armaroli, Inorg. Chem. 2018, 57, 15537-15549.
[51] Y.Q. Zou, J.R. Chen, X.P. Liu, L.Q. Lu, R.L. Davis, K.A. Jorgensen, W.J.
Xiao, Angew. Chem. Int. Ed. 2012, 51, 784-788.
[1]
[2]
[3]
[4]
[5]
T. Mirkovic, E.E. Ostroumov, J.M. Anna, R. van Grondelle, Govindjee,
G.D. Scholes, Chem. Rev. 2017, 117, 249-293.
S. Berardi, S. Drouet, L. Francas, C. Gimbert-Surinach, M. Guttentag, C.
Richmond, T. Stoll, A. Llobet, Chem. Soc. Rev. 2014, 43, 7501-7519.
A.S. Weingarten, A.J. Dannenhoffer, R.V. Kazantsev, H. Sai, D. Huang,
S.I. Stupp, J. Am. Chem. Soc. 2018, 140, 4965-4968.
C.K. Prier, D.A. Rankic, D.W. MacMillan, Chem. Rev. 2013, 113, 5322-
5363.
Y.J. Yuan, Z.T. Yu, D.Q. Chen, Z.G. Zou, Chem. Soc. Rev. 2017, 46,
603-631.
[6]
[7]
[8]
[9]
B. Chen, L.Z. Wu, C.H. Tung, Acc. Chem. Res. 2018, 51, 2512-2523.
C. Michelin, N. Hoffmann, ACS Catal. 2018, 8, 12046-12055.
V. Balzani, A. Juris, Coord. Chem. Rev. 2001, 211, 97-115.
I.M. Dixon, J.-P. Collin, J.-P. Sauvage, L. Flamigni, S. Encinas, F.
Barigelletti, Chem. Soc. Rev. 2000, 29, 385-391.
[10] A.T. Yeh, C.V. Shank, J.K. McCusker, Science 2000, 289, 935-938.
[11] A.K. Pal, G.S. Hanan, Chem. Soc. Rev. 2014, 43, 6184-6197.
[12] S. Ji, W. Wu, W. Wu, H. Guo, J. Zhao, Angew. Chem. Int. Ed. 2011, 50,
1626-1629.
[13] S. Monro, J. Scott, A. Chouai, R. Lincoln, R. Zong, R.P. Thummel, S.A.
McFarland, Inorg. Chem. 2010, 49, 2889-2900.
[14] T.P. Yoon, M.A. Ischay, J. Du, Nat. Chem. 2010, 2, 527-532.
[15] Y.Y. Zhu, G. Lan, Y. Fan, S.S. Veroneau, Y. Song, D. Micheroni, W. Lin,
Angew. Chem. Int. Ed. 2018, 57, 14090-14094.
[16] H. Huo, X. Shen, C. Wang, L. Zhang, P. Rose, L.A. Chen, K. Harms, M.
Marsch, G. Hilt, E. Meggers, Nature 2014, 515, 100-103.
[17] Y. Lu, J. Wang, N. McGoldrick, X. Cui, J. Zhao, C. Caverly, B. Twamley,
O.M. GM, B. Irwin, R. Conway-Kenny, S.M. Draper, Angew. Chem. Int.
Ed. 2016, 55, 14688-14692.
[18] P. Wang, S. Guo, H.J. Wang, K.K. Chen, N. Zhang, Z.M. Zhang, T.B.
Lu, Nat. Commun. 2019, 10, 3155.
[19] S.Y. Takizawa, R. Aboshi, S. Murata, Photochem. Photobiol. Sci. 2011,
10, 895-903.
[20] C. Fan, L. Wei, T. Niu, M. Rao, G. Cheng, J.J. Chruma, W. Wu, C.
Yang, J. Am. Chem. Soc. 2019, 141, 15070-15077.
[21] C.E. Whittle, J.A. Weinstein, M.W. George, K.S. Schanze, Inorg. Chem.
2001, 40, 4053-4062.
[22] H. Guo, M.L. Muro-Small, S. Ji, J. Zhao, F.N. Castellano, Inorg. Chem.
2010, 49, 6802-6804.
[23] P. Du, J. Schneider, P. Jarosz, R. Eisenberg, J. Am. Chem. Soc. 2006,
128, 7726-7727.
[24] J. Zhao, W. Wu, J. Sun, S. Guo, Chem. Soc. Rev. 2013, 42, 5323-5351.
[25] S. Guo, K.-K. Chen, R. Dong, Z.-M. Zhang, J. Zhao, T.-B. Lu, ACS
Catal. 2018, 8, 8659-8670.
[26] N. Zhang, K.-K. Chen, S. Guo, P. Wang, M. Zhang, J. Zhao, Z.-M.
Zhang, T.-B. Lu, Appl. Catal. B: Environ. 2019, 253, 105-110.
[27] O.S. Wenger, J. Am. Chem. Soc. 2018, 140, 13522-13533.
[28] C. Wang, Z. Xie, K.E. deKrafft, W. Lin, Doping, J. Am. Chem. Soc. 2011,
133, 13445-13454.
[29] P. Chabera, Y. Liu, O. Prakash, E. Thyrhaug, A.E. Nahhas, A. Honarfar,
S. Essen, L.A. Fredin, T.C. Harlang, K.S. Kjaer, K. Handrup, F. Ericson,
H. Tatsuno, K. Morgan, J. Schnadt, L. Haggstrom, T. Ericsson, A.
Sobkowiak, S. Lidin, P. Huang, S. Styring, J. Uhlig, J. Bendix, R.
Lomoth, V. Sundstrom, P. Persson, K. Warnmark, Nature 2017, 543,
695-699.
[30] Y. Zhang, J.L. Petersen, C. Milsmann, J. Am. Chem. Soc. 2016, 138,
13115-13118.
[31] I. Ghosh, J. Khamrai, A. Savateev, N. Shlapakov, M. Antonietti, B.
Konig, Science 365, 2019, 360-366.
[32] J. Zhao, K. Xu, W. Yang, Z. Wang, F. Zhong, Chem. Soc. Rev. 2015,
44, 8904-8939.
[33] A. Hossain, A. Bhattacharyya, O. Reiser, Science 2019, 364.
This article is protected by copyright. All rights reserved.

10.1002/anie.202003251
Angewandte Chemie International Edition
RESEARCH ARTICLE
RESEARCH ARTICLE
Through-bond
strategy was first employed to
construct low-cost copper(I)
energy
transfer
Kai-Kai Chen, Song Guo,* Heyuan Liu,
Xiyou Li, Zhi-Ming Zhang,* and Tong-Bu
Lu
photosensitizer (PS) with strong
visible light harvesting ability and long-
lived excited state. Their performance
for energy and electron-transfer
Page No. – Page No.
Strong
Visible
Light-Absorbing
Cuprous Sensitizers for Dramatically
Boosting Photocatalysis
reactions
both
dramatically
outperforms that of traditional Cu-PS
2+
and noble-metal PSs (Ru(bpy)3 and
+
Ir(ppy)3 ).
This article is protected by copyright. All rights reserved.