Molecular Iridium Complexes in Metal-Organic Frameworks Catalyze CO2 Hydrogenation via Concerted Proton and Hydride Transfer

Article abstract of DOI:10.1021/jacs.7b10922

Molecular iridium catalysts immobilized in metal-organic frameworks (MOFs) were positioned in the condensing chamber of a Soxhlet extractor for efficient CO₂ hydrogenation. Droplets of hot water seeped through the MOF catalyst to create dynamic gas/liquid interfaces which maximize the contact of CO₂, H₂, H₂O, and the catalyst to achieve a high turnover frequency of 410 h^-1 under atmospheric pressure and at 85 °C. H/D kinetic isotope effect measurements and density functional theory calculations revealed concerted proton-hydride transfer in the rate-determining step of CO₂ hydrogenation, which was difficult to unravel in homogeneous reactions due to base-catalyzed H/D exchange.

Full text of DOI:10.1021/jacs.7b10922

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Communication
Molecular Iridium Complexes in Metal-Organic Frameworks Catalyze
2
CO Hydrogenation via Concerted Proton and Hydride Transfer
Bing An, Lingzhen Zeng, Mei Jia, Zhe Li, Zekai Lin, Yang
Song, Yang Zhou, Jun Cheng, Cheng Wang, and Wenbin Lin
J. Am. Chem. Soc., Just Accepted Manuscript • DOI: 10.1021/jacs.7b10922 • Publication Date (Web): 28 Nov 2017
Downloaded from http://pubs.acs.org on November 28, 2017
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Molecular Iridium Complexes in Metal-Organic Frameworks Cata-
lyze CO Hydrogenation via Concerted Proton and Hydride Transfer
2
‡
, [a]
‡, [a]
Mei Jia,‡, [a] Zhe Li, Zekai Lin, Yang Song, Yang Zhou, Jun
[a]
[b]
[b]
[a]
Bing An,
Lingzhen Zeng,
Cheng,* Cheng Wang, and Wenbin Lin
[a]
*[a]
*[a,b]
[a]
Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid
Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005,
PR China
[b]
Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
Supporting Information Placeholder
Importantly, performing the reactions with D
2 2
and/or D O in
ABSTRACT: Molecular iridium catalysts immobilized in metal-
organic frameworks (MOFs) were positioned in the condensing
place of H and/or H O under neutral pH revealed ultralarge H/D
2
2
kinetic isotope effects (KIEs) which were previously masked by
base-catalyzed H/D exchange in homogeneous systems. The ultra-
large KIEs for CO hydrogenation suggest concerted proton-hy-
2
dride transfer via quantum tunneling in the rate-determining step
(RDS), which was further supported by density functional theory
DFT) calculations.
chamber of a Soxhlet extractor for efficient CO
Droplets of hot water seeped through the MOF catalyst to create
dynamic gas/liquid interfaces which maximize the contact of CO
, H O, and the catalyst to achieve a high turnover frequency of
2
hydrogenation.
2
,
H
2
2
-1
o
4
10 h under atmospheric pressure and at 85 C. H/D kinetic iso-
(
tope effect measurements and density functional theory calcula-
tions revealed concerted proton-hydride transfer in the rate-deter-
mining step of CO
2
hydrogenation, which was difficult to unravel
in homogeneous reactions due to base-catalyzed H/D exchange.
Hydrogenation of CO
est, not only as an attractive path to convert CO
icals, but also as a key step in hydrogen storage using HCO
2
to formic acid (HCO
2
H) is of great inter-
to platform chem-
H as a
2
2
1
chemical carrier. However, low solubility of hydrogen in water has
2
limited the catalytic turnover frequency (TOF). Herein, we report
the design of metal-organic framework (MOF) catalysts for effi-
cient CO hydrogenation in a Soxhlet-type reflux-condensing sys-
2
tem. Solid MOF catalysts were packed in a plate that was located
below the condenser. Droplets of hot condensed water passed
through the catalyst bed intermittently, creating a dynamic
gas/liquid/solid interface to maximize the contact among CO
2 2
, H ,
2
H O, and the catalyst to produce formic acid (Scheme 1). The
Scheme 1. Schematic showing
a Soxhlet-type reflux-
generated formic acid in the aqueous solution was then siphoned to
the refluxing flask and neutralized by sodium bicarbonate to
condensing system to place MOF catalysts at a dynamic tri-
phasic interface of CO
2
/H
2
-H
2
O-catalyst for CO
2
hydrogenation
formate, pushing the chemical equilibrium of H
HCO H (aq) to the right.
Key to this reaction design is the construction of solid MOF cat-
2 2
(g) + CO (g) =
to formate.
2
H bpydcOH was prepared from H bpydc in four steps in a 22%
2 2
overall yield (see Supporting Information [SI] for details, Figure
S1-11). The hydroxyl group in bpydcOH serves as an electron do-
nating group and a hydrogen bonding site, which has been reported
to facilitate CO
Less sterically demanding 4,4'-biphenyl-dicarboxylic acid (H
was mixed with H bpydcOH or H bpydc in MOF synthesis to pre-
serve open channels in metalated MOFs. The reaction between the
3
4
5
6
alysts based on molecular functionalities. A number of Ru , Rh ,
7
8
9
10
Ir , Co , Re and Fe complexes have been reported to be highly
active in CO hydrogenation, among which Ir-polypyridine based
2
11
2
hydrogenation in homogeneous Ir complexes.
11
complexes form a versatile category. We incorporated Ir com-
plexes into UiO-type MOFs using 2,2’-bipyridine-5,5’-dicarbox-
ylate ligands with or without -OH substitution on the 6-position
2
bpdc)
2
2
(
bpydcOH or bpydc) to provide isolated anchoring sites for Ir. After
o
ligand mixture and ZrCl
4
in dimethylformamide (DMF) at 120 C
(μ -O) (μ
as secondary building units (SBUs) (Figure 1a,b).
activation, the Ir complexes immobilized in MOFs exhibit high ac-
yielded mbpyOH-UiO and mbpy-UiO MOFs with [Zr
OH) ]
4
6
3
4
3
-
tivity to hydrogenate CO
up.
2
to formate in the reflux-condensing set-
12+
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The UiO-type MOF structures of mbpyOH-UiO and mbpy-UiO
were revealed by the similarity of their powder X-ray diffraction
The catalytic activities of mbpyOH-IrCl
UiO in CO hydrogenation were evaluated in the Soxhlet-type re-
flux-condensing system. The bottom flask contained a basic aque-
ous solution of 1 M NaHCO . After a reaction of 15 hours, formate
was detected in the bottom flask by H-NMR and quantified by
high performance liquid chromatography (HPLC) (Table 1, entries
1&2; Figure S28-30). No gaseous product was detected in the head-
3 3
-UiO and mbpy-IrCl -
2
1
2
(
PXRD) patterns to that of UiO-67 (Figure S12). Transmission
electron microscopy (TEM) showed octahedral nanocrystals of the
MOFs (Figure S13-14). Chemical formulae of these MOFs were
established by a combination of thermogravimetric analyses to de-
termine mass ratios of metal/organics (Figure S15-16) and proton
3
1
0
1
2
3
4
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1
nuclear magnetic resonance ( H NMR) spectra of digested MOFs
space by gas chromatography (Figure S31). mbpyOH-IrCl
3
-UiO
in NaOD/D
Figure S17-18). We obtained chemical formulae of Zr
OH) (bpdc)2.67(bpydcOH)2.67(HCO 1.33 for mbpyOH-UiO and
Zr ( -O) ( -OH) (bpdc)2.07(bpydc)3.10(HCO 1.66 for mbpy-UiO.
Postsynthetic metalation of the MOFs with IrCl ·3H O in a
mixture of tetrahydrofuran (THF) and DMF gave metalated MOFs
mbpyOH-IrCl -UiO and mbpy-IrCl -UiO with bpyOH-IrCl (THF)
and bpy-IrCl (THF) moieties, respectively. Ir loading levels
determined by inductively coupled plasma-mass spectrometry
ICP-MS) correspond to incorporation of 10.5 mol% of Ir on the
bpyOH sites in mbpyOH-IrCl -UiO and 13.7 mol% of Ir on the bpy
sites in mbpy-IrCl -UiO. PXRD patterns showed that both
2
O to quantify amounts of ligands and capping formates
gave an Ir-based turnover number (Ir-TON) of 543±35 in 15 h with
-1
(
6
( -O) (
3
4
3
-
an average Ir-TOF of 36±2 h under one atmosphere of H
2 2
/CO =
4
2
)
1/1, while mbpy-IrCl -UiO afforded an Ir-TON of 23±4 and an Ir-
3
)
TOF of 1.5±0.2. Control experiments with non-metalated
mbpyOH-UiO or mbpy-UiO gave no products (Table 1, entries
6
3
4
3
4
2
3
2
3&4), confirming the role of Ir as the catalytic center. The temper-
ature of the condensed water at the catalyst bed was measured to be
3
3
3
o
8
5 C.
3
3
Monitoring the Ir-TONs of mbpyOH-IrCl -UiO over time re-
vealed an induction period of approximately 8 hours, suggesting
(
III
the need to transform the bpyOH-Ir Cl
tive form, which possibly involves breaking Ir-Cl bonds. To facili-
tate chloride removal, mbpyOH-IrCl -UiO and mbpy-IrCl -UiO
were treated with NaBHEt followed by air oxidation to yield
3
(solvent) species to an ac-
3
3
metalated MOFs remained crystalline (Figure S12). Nitrogen sorp-
3
3
2
tion experiments gave BET surface areas of 705 m /g for mbpyOH-
3
2
III
III
Ir-UiO and 843 m /g for mbpy-Ir-UiO, respectively (Figure S19).
mbpyOH-[Ir ]-UiO and mbpy-[Ir ]-UiO (Figure 1a). A mixture
III
III
+
2 2 2 2 3
of [bpyO-Ir Cl (OH ) ], [bpyO-Ir Cl(OH ) ] , and [bpyO-
Ir (OH)(OH ) ] were present in mbpyOH-[Ir ]-UiO with differ-
2 3
III
+
III
ent extents of chloride removal (Figure S23-26). In the following
-
III
+
discussions, we focus on the [bpyO -Ir (OH)(OH
2
)
3
] species as a
-
representative site. The degree of deprotonation of [bpyO -
Ir (OH)(OH ) ] was based on DFT calculation of pKa values of
2 3
III
+
protons in each coordinated water and the hydroxyl group on the
ligand (Figure S53-55).
Table 1. Hydrogenation of CO
alysts.
2
to formate using different cat-
TONb
b
Entry Catalyst
Ir
wt%
TOF
(h )
-
1
1a
mbpyOH-IrCl
3
-UiO
2.6
3.8
-
543±35
23±4
36±2
2a
3a
4a
5a
6a
7a
mbpy-IrCl -UiO
1.5±0.2
3
mbpyOH-UiO
mbpy-UiO
no formate
no formate
6149±50
417±22
0
-
-
-
III
mbpyOH-[Ir ]-UiO
2.4
3.8
100
2.4
31
410±3
III
mbpy-[Ir ]-UiO
28±2
Ir-NP
0
0
8c
9d
mbpyOH-[Ir ]-UiO
III
0
III
III
Figure 1. a) Preparation of mbpyOH-[Ir ]-UiO and mbpy-[Ir ]-
e
f
e
III
bpydcOH-IrCl
3
(OH
2
)
13/11 /8
0.9/0.7 /
UiO catalysts. b) local structure of mbpyOH-[Ir ]-UiO. c) EXAFS
spectra of mbpyOH-[Ir ]-UiO at the Ir LIII-edge together with the
f
III
0.5
10c
bpydcO -IrCp*OH
-
18.4
0
0
fittings in R-space, showing the magnitude (hollow squares, red)
and the real (hollow squares, blue) components. The fitting range
is 1.0–3.0 Å in R space (within the black line).
1d
-
1
bpydcO -IrCp*OH
18.4 256±10
17.0±0.7
aReaction conditions: 5 mg of catalysts in reflux-condensing sys-
tem, 0.1 MPa H /CO = 1, 1 M NaHCO (aq) in bottom flask, temp.
2 2 3
Local coordination environments of Ir in MOFs were probed by
X-ray absorption spectroscopy (XAS) at the Ir LIII-edge. X-ray ab-
o
b
c
=
85 C, time = 15 h. TON and TOF are both based on Ir. 10 mg
of catalysts, 10 mL of 1 M NaHCO (aq) in a flask, 0.1 MPa H /CO
1, temp. = 85 C, time = 15 h. 10 mg of catalysts, 10 mL of 1 M
sorption near edge structure (XANES) of mbpyOH-IrCl
3
-UiO con-
3
2
2
III
firmed the oxidation state of Ir by a rising edge similar to that of
o
d
=
IrCl
3
(main peak at 11217 eV) (Figure S20).4 Fittings of the ex-
e
o
3 2 2
NaHCO (aq) in a bomb, 1 MPa H /CO = 1, temp. = 85 C, time =
tended X-ray absorption fine structure (EXAFS) regions afforded
six-coordinated Ir centers with two nitrogen atoms from bipyridine
moiety, three chlorides, and one oxygen atom from a THF molecule
in the first coordination sphere (Figure S21-22).
e
f
1
5 h. with NaHBEt
3
3
with AgNO .
III
The activated mbpyOH-[Ir ]-UiO gave much higher catalytic
activity than the unactivated one, achieving an Ir-TON of 6149±50
-1
in 15 hours and an Ir-TOF of 410±3 h (Table 1, entry 5, Figure
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S32) with a shorter induction period of ~3 h (Figure 2a). These
TON and TOF values compare favorably with other catalysts for
CO hydrogenation at ambient pressure (Table S6).
On the other hand, when D
2
was used in the gas phase and H
2
O
was used as the solvent, DCO
2
Na was exclusively produced for
III
III
2
both mbpyOH-[Ir ]-UiO and mbpy-[Ir ]-UiO (Figure S43-44),
-
again confirming that the deuterium in DCO
2
originated from D
2
.
The KIE (H O/H -H O/D ) value ([rate with H
2
2
2
2
2
]/[rate with D ])
2
III
III
was 19 for mbpyOH-[Ir ]-UiO and 5.9 for mbpy-[Ir ]-UiO. Such
III
a KIE value over 10 for mbpyOH-[Ir ]-UiO also indicates nuclear
1
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0
tunneling during the hydride transfer to CO
When the reaction was carried out using a combination of D
the gas phase and D O in the aqueous phase, negligible amount of
formate was produced with mbpyOH-[Ir ]-UiO (Figure S45-46),
affording an overall KIE (H /H O-D /D O) value of over 3000,
which is no less than the product of KIE (H O/H -D O/H ) and KIE
(H O/H -H O/D ). This is only possible when proton transfer and
hydride transfer to CO
the double deuterium experiment for mbpy-[Ir ]-UiO gave a KIE
2
.
2
in
2
III
2
2
2
2
2
2
2
2
Figure 2. Catalytic data of the Ir-based catalysts: a) TONs as a
function of reaction time; b) KIE values under different conditions.
2
2
2
2
1
4
2
take place in the same RDS. Similarly,
III
III
mbpyOH-[Ir ]-UiO was recovered and reused for at least three
times without obvious loss of catalytic activity (Figure S34). The
(H
(H
2
/H
O/H
2
O-D
-D
2
/D
O/H
2
O) value over 45, larger than the product of KIE
) and KIE (H O/H -H O/D ).
III
recovered mbpyOH-[Ir ]-UiO after catalysis remained crystalline,
2
2
2
2
2
2
2
2
as shown by PXRD patterns (Figure S12). The oxidation state of
III
III
Ir in mbpyOH-[Ir ]-UiO remained unchanged based on XANES
and XPS studies (Figure S20, 26). ICP-MS analyses of the aqueous
solution in the refluxing flask showed negligible metal leaching
(0.18% of Ir and 0.05% of Zr). Importantly, a second 15 h reaction
of this solution produced no additional products, proving that the
III
mbpyOH-[Ir ]-UiO instead of the leached species was the active
catalyst. Control experiments using Ir nanoparticles (Ir-NP) did not
give any CO hydrogenation products (Table 1, entry 7; Figure
2
S35-36), ruling out Ir-NPs as catalysts.
The reflux-condensing system for placing the catalysts at liquid-
gas interface greatly enhanced their TOFs compared to catalysis
III
with the same catalysts in solutions. For example, mbpyOH-[Ir ]-
3
UiO in a 1 M NaHCO solution generated negligible amounts of
o
formate at 85 C (Table 1, entry 8), in part due to the decomposition
of the MOF in basic solutions. Furthermore, homogeneous
molecular bpydcOH-IrCl
3
(OH
2
) complex with or without treatment
-1
with NaBHEt or AgNO
3
3
gave low activities with TOFs of <1 h
at gas pressures of 1 MPa (Table 1, entry 9). The homogeneous
catalysts may form inactive dimers or oligomers, which is
prevented in MOFs due to active site isolation on the framework.
Consistent with this hypothesis, introduction of
pentamethylcyclopentadiene (Cp*) group in the complex bpydcO
IrCp*OH slowed catalyst deactivation to afford a moderate Ir-
a bulky
-
-
TON of 256±10 in 15 h at a gas pressure of 1 MPa and a
o
temperature of 85 C (Table 1, entry 11, Figure S37), which is still
III
much lower than that of mbpyOH-[Ir ]-UiO in the reflux-
condensing setup at a gas pressure of 0.1 MPa.
III
The enhanced activity of mbpyOH-[Ir ]-UiO over that of mbpy-
III
[Ir ]-UiO by 11 times (Table1, entry 6, Figure S33) demonstrated
the importance of hydroxyl group on the bpyOH ligand.1 To fur-
3
ther probe the mechanism, we measured solvent KIEs (Figure 2b,
S38-40) by comparing the reaction rates using D
separate experiments. HCO Na but not DCO Na was produced
with D O in the bottom flask and H in the headspace for both
2 2
O vs. H O in two
2
2
2
2
Figure 3. a) Proposed mechanism for the hydrogenation of CO
2
III
III
1
III
mbpyOH-[Ir ]-UiO and mbpy-[Ir ]-UiO as revealed by H NMR
by mbpyOH-[Ir ]-UiO with activation enthalpies (see SI). b)
2
and H NMR (Figure S41-42). These results suggest that hydrogen
Calculated free-energy profiles for the proposed catalytic cycle for
CO hydrogenation to formic acid.
2
in formate comes from H
ting of H generates iridium hydride species, formates must be pro-
duced from CO via a hydride transfer step. Importantly, a dramatic
reduction of reaction rate was observed using D O as the solvent
with a large KIE (H O/H -D O/H ) value ([rate in H O]/[rate in
O]) of 140 for mbpyOH-[Ir ]-UiO. Such a large KIE value is
only possible when quantum tunneling of proton is involved in the
2
in the gas phase. As the heterolytic split-
2
Based on these experimental observations, we propose a cata-
lytic cycle which is supported by DFT calculations as shown in
2
2
*
Figure 3. The transition states of H
2
heterolysis (A ) and proton-
2
2
2
2
2
*
-
III
hydride transfer (C ) gave activation energies of Ea1=0.34 kcal∙mol
D
2
1
-1
and Ea2=16.26 kcal∙mol respectively, supporting the proton-hy-
III
dride transfer to be the RDS. The corresponding energy profiles are
shown in Figure 3b. The equilibria between B/C and D/A depend
RDS. In contrast, mbpy-[Ir ]-UiO gave a KIE (H
value of 7.8.
2 2 2 2
O/H -D O/H )
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on the reaction pH and the pKa’s of B and A (Figure S57). In addi-
REFERENCES
tion, calculated H/D KIE value considering only zero-point ener-
gies gave a small number of ~2, suggesting that the quantum tun-
neling effect plays a key role in the experiment. Similar concerted
proton and hydride transfer has been previously reported for the
alcohol dehydrogenase and an Os complex.15
It is worth noting that the homogeneous catalyst bpydcO--
IrCp*OH in basic solution gave different isotope distributions in
1
(a) Klankermayer, J.; Leitner, W., Science 2015, 350, 629-630; (b)
Jessop, P. G.; Joo, F.; Tai, C.-C., Coord. Chem. Rev. 2004, 248, 2425-2442;
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(
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3
(a) Kornienko, N.; Zhao, Y.; Kley, C. S.; Zhu, C.; Kim, D.; Lin, S.;
products. With both H
catalyst produced a mixture of DCO
DCO Na/HCO Na ratios of 0.80 and 0.98 respectively (Figure
2
O/D
2
and D
2
2
O/H , the homogeneous
Chang, C. J.; Yaghi, O. M.; Yang, P., J. Am. Chem. Soc. 2015, 137, 14129-
14135; (b) Chen, X.; Jiang, H.; Hou, B.; Gong, W.; Liu, Y.; Cui, Y., J Am
Chem Soc 2017, 139, 13476-13482; (c) Zeng, L.; Guo, X.; He, C.; Duan,
C., ACS Catal. 2016, 6, 7935-7947; (d) Fei, H.; Cohen, S. M., Chem.
Commun. 2014, 50, 4810-4812; (e) Hong, D.-Y.; Hwang, Y. K.; Serre, C.;
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J.; Kapteijn, F., J. Catal. 2012, 289, 42-52.
2
Na and HCO
2
Na with the
2
2
S47-52). This D/H exchange likely results from base-assisted
reductive elimination of the slightly protonic Ir-H(D) bond to
I
produce Ir species, which can be further protonated by D
2
O(H
2
O)
to regenerate Ir-D(H). The D/H exchange masked the KIE to give
moderate apparent values of 1.1 and 1.6 with H
respectively.
2
O/D
2
2 2
and D O/H ,
4
(a) Xu, H.-Q.; Hu, J.; Wang, D.; Li, Z.; Zhang, Q.; Luo, Y.; Yu, S.-H.;
In summary, we performed efficient catalytic CO
tion to form formic acid/formate by placing MOF catalysts in a
Soxhlet-type reflux-condensing system. Replacing H and/or H
by D and/or D O in the reaction revealed ultralarge H/D KIEs by
2
hydrogena-
Jiang, H.-L., J. Am. Chem. Soc. 2015, 137, 13440-13443; (b) Feng, D.;
Chung, W.-C.; Wei, Z.; Gu, Z.-Y.; Jiang, H.-L.; Chen, Y.-P.; Darensbourg,
D. J.; Zhou, H.-C., J. Am. Chem. Soc. 2013, 135, 17105-17110; (c)
Korzyński, M. D.; Dincă, M., ACS Cent. Sci. 2017, 3, 10-12; (d) Yang, D.;
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L.; Gates, B. C., J. Am. Chem. Soc. 2015, 137, 7391-7396; (e) Wang, C.;
Xie, Z.; de Krafft, K. E.; Lin, W., J. Am. Chem. Soc. 2011, 133, 13445-
2
2
O
2
2
preventing base-catalyzed H/D exchange in homogeneous reac-
tions. The ultralarge KIEs and DFT calculations suggest concerted
proton-hydride transfer in the rate-determining step of CO hydro-
2
genation. This work highlights opportunities to use MOFs as solid
molecular catalysts in designer reactors to improve catalytic con-
versions and to uncover interesting mechanistic details.
1
1
3454; (f) Wang, C.; Liu, D.; Lin, W., J. Am. Chem. Soc. 2013, 135, 13222-
3234.
5 (a) Kajiwara, T.; Fujii, M.; Tsujimoto, M.; Kobayashi, K.; Higuchi, M.;
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028-1031.
Himeda, Y.; Miyazawa, S.; Hirose, T., ChemSusChem 2011, 4, 487-
ASSOCIATED CONTENT
Supporting Information
6
493.
7
(a) Hull, J. F.; Himeda, Y.; Wang, W.-H.; Hashiguchi, B.; Periana, R.;
Experimental procedures; spectroscopic characterization of pre-
catalysts and catalysts; X-Ray absorption spectroscopic analysis;
evaluation of catalytic performances; KIEs and quantifications of
HCOOH and DCOOH and DFT calculations. This material is avail-
able free of charge via the Internet at http://pubs.acs.org.
Szalda, D. J.; Muckerman, J. T.; Fujita, E., Nat. Chem. 2012, 4, 383-388;
b) Tanaka, R.; Yamashita, M.; Nozaki, K., J. Am. Chem. Soc. 2009, 131,
(
14168-14169.
8 Jeletic, M. S.; Mock, M. T.; Appel, A. M.; Linehan, J. C., J. Am. Chem.
Soc. 2013, 135, 11533-11536.
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(a) Sato, S.; Koike, K.; Inoue, H.; Ishitani, O., Photochem. Photobiol.
Sci. 2007, 6, 454-461; (b) Morris, A. J.; Meyer, G. J.; Fujita, E., Acc. Chem.
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AUTHOR INFORMATION
Author Contributions
1
0 Boddien, A.; Mellmann, D.; Gärtner, F.; Jackstell, R.; Junge, H.;
Dyson, P. J.; Laurenczy, G.; Ludwig, R.; Beller, M., Science 2011, 333,
1733-1736.
‡
These authors contributed equally.
11 Wang, W.-H.; Hull, J. F.; Muckerman, J. T.; Fujita, E.; Himeda, Y.,
Corresponding Author
Energy Environ. Sci. 2012, 5, 7923.
12 Cavka, J. H.; Jakobsen, S.; Olsbye, U.; Guillou, N.; Lamberti, C.;
Bordiga, S.; Lillerud, K. P., J. Am. Chem. Soc. 2008, 130, 13850-13851.
wangchengxmu@xmu.edu.cn
wenbinlin@uchicago.edu
chengjun@xmu.edu.cn
1
3 (a) Dub, P. A.; Gordon, J. C., ACS Catal. 2017, 7, 6635-6655; (b)
Belkova, N. V.; Epstein, L. M.; Filippov, O. A.; Shubina, E. S., Chem Rev
2
016, 116, 8545-8587.
ACKNOWLEDGMENT
14 O'Leary, M. H., Annu. Rev. Biochem 1989, 58, 377-401.
1
5 (a) Agarwal, P. K.; Webb, S. P.; Hammes-Schiffer, S., J. Am. Chem.
We acknowledge funding support from the National Natural Sci-
ence Foundation and Ministry of Science and Technology of the P.
R. China (NSFC21671162, 2016YFA0200702, NSFC21471126，
NSFC21373166，NSFC21621091), the National Thousand Tal-
ents Program of the P. R. China, and Xiamen University and the
US National Science Foundation (DMR-1308229).
Soc. 2000, 122, 4803-4812; (b) Nagorski, R. W.; Richard, J. P., J. Am. Chem.
Soc. 2001, 123, 794-802; (c) Cui, Q.; Elstner, M.; Karplus, M., J. Phys.
Chem. B 2002, 106, 2721-2740; (d) Ess, D. H.; Schauer, C. K.; Meyer, T.
J., J. Am. Chem. Soc. 2010, 132, 16318-16320.
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