Page 5 of 7
ACS Catalysis
ꢀ
1
Carbon Dioxide. Nature 2013, 495, 85‒89. (b) Rodríguezꢀ
formaldehyde (3 mol L , 20 mL H
C (oil bath temperature).
2
O), 4 ꢀmol catalyst 4, 95
1
2
3
4
5
6
7
8
9
°
Lugo, R. E.; Trincado, M.; Vogt, M.; Tewes, F.; Santisoꢀ
Quinones, G.; Grützmacher, H. A Homogeneous Transition
Metal Complex for Clean Hydrogen Production from Methaꢀ
nol–Water Mixtures. Nat. Chem. 2013, 5, 342‒347. (c) Hu, P.;
DiskinꢀPosner, Y.; BenꢀDavid, Y.; Milstein, D. Reusable Homoꢀ
geneous Catalytic System for Hydrogen Production from Methꢀ
anol and Water. ACS Catal. 2014, 4, 2649‒2652. (d) Bielꢀ
inski, E. A.; Förster, M.; Zhang, Y.; Bernskoetter, W. H.;
Hazari, N.; Holthausen, M. C. BaseꢀFree Methanol Dehydroꢀ
genation Using a PincerꢀSupported Iron Compound and Lewis
Acid Coꢀcatalyst. ACS Catal. 2015, 5, 2404‒2415. (e) Klankerꢀ
mayer, J.; Wesselbaum, S.; Beydoun, K.; Leitner, W. Selective
Catalytic Synthesis Using the Combination of Carbon Dioxide
and Hydrogen: Catalytic Chess at the Interface of Energy and
Chemistry. Angew. Chem. Int. Ed. 2016, 55, 7296‒7343. (f)
Kothandaraman, J.; Kar, S.; Sen, R.; Goeppert, A.; Olah, G. A.;
Prakash, G. K. S. Efficient Reversible Hydrogen Carrier System
Based on Amine Reforming of Methanol. J. Am. Chem.
Soc. 2017, 139, 2549‒2552.
Based on the results observed in Figure S8 and Table
S5, a formaldehyde concentration of 3 mol L was selectꢀ
ed as the optimal concentration for obtaining high H
yield, as well as high TOF and TON. The time course of
the TON for hydrogen production under additiveꢀfree
conditions was carried out (Figure 4). A high TOF of
8300 h (average TOF over initial 5 min) was achieved.
Remarkably, catalyst 4 is highly robust under the applied
conditions. A maximum TON of 24000 was obtained
after 100 h, affording a yield of ∼80%.
ꢀ
1
2
ꢀ
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
In conclusion, to the best of our knowledge, the highꢀ
est TON and selectivity yet reported for H production
2
from aqueous formaldehyde under mild conditions withꢀ
out using any additive or organic solvent were obtained
with catalyst 4. Moreover, mechanistic studies suggest
that the formation of ruthenium hydride is the rate deꢀ
termining step for the dehydrogenation of aqueous forꢀ
maldehyde. Remarkably, the NꢀH moieties on the coorꢀ
dinated ruthenium complex are crucial to greatly enꢀ
hance the catalytic activity. The present catalytic system,
combined with the detailed mechanistic investigations
will provide new opportunities for developing highꢀ
(
4)
(a) Bertini, F.; Mellone, I.; Ienco, A.; Peruzzini, M.;
Gonsalvi, L. Iron(II) Complexes of the Linear racꢀTetraphosꢀ1
Ligand as Efficient Homogeneous Catalysts for Sodium Bicarꢀ
bonate Hydrogenation and Formic Acid Dehydrogenation. ACS
Catal. 2015, 5, 1254‒1265. (b) Hull, J. F.; Himeda, Y.; Wang, W.
H.; Hashiguchi, B.; Periana, R.; Szalda, D. J.; Muckerman, J. T.;
2
Fujita, E. Reversible Hydrogen Storage Using CO and a Proꢀ
tonꢀSwitchable Iridium Catalyst in Aqueous Media under Mild
Temperatures and Pressures. Nat. Chem. 2012, 4, 383‒388. (c)
Wang, W. H.; Himeda, Y.; Muckerman, J. T.; Manbeck, G. F.;
Fujita, E. CO2 Hydrogenation to Formate and Methanol as an
performance homogeneous catalysts for effective H
production from the liquid organic hydrogen carriers.
2
Alternative to Photoꢀ and Electrochemical CO
2
Reduction.
ASSOCIATED CONTENT
Chem. Rev. 2015, 115, 12936‒12973. (d) Wang, L.; Onishi, N.;
Murata, K.; Hirose, T.; Muckerman, J. T.; Fujita, E.; Himeda, Y.
Efficient Hydrogen Storage and Production Using a Catalyst
with an ImidazolineꢀBased, ProtonꢀResponsive Ligand.
ChemSusChem 2017, 10, 1071‒1075. (e) Li, Z. P.; Xu, Q. Metalꢀ
NanoparticleꢀCatalyzed Hydrogen Generation from Formic
Acid. Acc. Chem. Res. 2017, 50, 1449‒1458. (f) Papp, G.;
Csorba, J.; Laurenczy, G.; Joó, F. A Charge/Discharge Device
for Chemical Hydrogen Storage and Generation. Angew. Chem.
Int. Ed. 2011, 50, 10433‒10435. (g) Huff, C. A.; Sanford, M. S.
Supporting Information. This material is available free
mental section including general methods, supplemental
data, and computational details.
AUTHOR INFORMATION
Corresponding Authors
*
*
2
Catalytic CO Hydrogenation to Formate by a Ruthenium Pinꢀ
cer Complex. ACS Catal. 2013, 3, 2412‒2416. (h) Lu, S. M.;
ORCID
Wang, Z. J.; Li, J.; Xiao, J. L.; Li, C. Baseꢀfree hydrogenation of
CO to formic acid in water with an iridium complex bearing a
2
N,N’ꢀdiimine ligand. Green Chem. 2016,18, 4553‒4558. (i)
Burgess, S. A.; Appel, A. M.; Linehan, J. C.; Wiedner, E. S.
Lin Wang: 0000ꢀ0001ꢀ5644ꢀ8865
Mehmed Z. Ertem: 0000ꢀ0003ꢀ1994ꢀ9024
Etsuko Fujita: 0000ꢀ0002ꢀ0407ꢀ6307
Yuichiro Himeda: 0000ꢀ0002ꢀ9869ꢀ5554
Changing the Mechanism for CO
2
Hydrogenation Using
Solvent‐Dependent Thermodynamics. Angew. Chem. Int. Ed.
2017, 56,15002‒15005. (j) Bernskoetter, W. H.; Hazari,
N. Reversible Hydrogenation of Carbon Dioxide to Formic Acid
and Methanol: Lewis Acid Enhancement of Base Metal Cataꢀ
lysts. Acc. Chem. Res. 2017, 50, 1049‒1058. (k) Guan C.; Zhang,
D.ꢀD.; Pan, Y. P.; Iguchi, M.; Ajitha, M. J.; Hu, J. S.; Li, H. F.;
Yao, C. G.; Huang, M. ꢀH.; Min, S. X.; Zheng, J. R.; Himeda, Y.;
Kawanami, H.; Huang, K.ꢀW. Dehydrogenation of Formic Acid
Catalyzed by a Ruthenium Complex with an N,N′ꢀDiimine Ligꢀ
and. Inorg. Chem. 2017, 56, 438‒445. (l) Singh, A. K.; Singh, S.;
Kumar, A. Hydrogen Energy Future with Formic Acid: a Reꢀ
newable Chemical Hydrogen Storage System. Catal. Sci. Tech-
nol. 2016, 6, 12ꢀ40. (m) Mellmann, D.; Sponholz, P.; Junge, H.;
Beller, M. Formic Acid as a Hydrogen Storage Material–
Development of Homogeneous Catalysts for Selective Hydrogen
Release. Chem. Soc. Rev. 2016, 45, 3954ꢀ3988. (n) Eppinger, J.;
Huang, K.ꢀW. Formic Acid as a Hydrogen Energy Carrier. ACS
Energy Lett. 2017, 2, 188–195. (o) Sordakis, K.; Tang, C. H.;
Vogt, L. K.; Junge, H.; Dyson, P. J.; Beller, M.; Laurenczy, G.
Homogeneous Catalysis for Sustainable Hydrogen Storage in
Formic Acid and Alcohols. Chem. Rev. 2018, 118 , 372‒433.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
This work was supported by ENEOS Hydrogen Trust Fund.
The work at BNL was carried out with support from the U.S.
Department of Energy, Office of Science, Division of Chemiꢀ
cal Sciences, Geosciences & Biosciences, Office of Basic Enꢀ
ergy Sciences under contract DEꢀSC0012704.
REFERENCES
(1)
ence 1972, 176, 1323.
2) Sartbaeva, A.; Kuznetsov, V. L.; Wells, S. A.; Edwards,
Bockris, J. O’M. A Hydrogen Economy. Sci-
(
P. P. Hydrogen Nexus in a Sustainable Energy Future. Energy
Environ. Sci. 2008, 1, 79‒85.
(3)
H.ꢀJ.; Junge, H.; Gladiali, S.; Beller, M. LowꢀTemperature
AqueousꢀPhase Methanol Dehydrogenation to Hydrogen and
(a) Nielsen, M.; Alberico, E.; Baumann, W.; Drexler,
ACS Paragon Plus Environment