Enhancing Cooperativity in Bifunctional Acid–Pd Catalysts with Carboxylic Acid-Functionalized Organic Monolayers
Abstract
Here, cooperative catalysts containing a combination of noble metal hydrogenation sites and Bronsted acid sites are critical for many reactions, including the deoxygenation (DO) of biomass-derived oxygenates in the upgrading of pyrolysis oil. One route toward the design of cooperative catalysts is to tether two different catalytically active functions so that they are in close proximity while avoiding undesirable interactions that can block active sites. Here, we deposited carboxylic acid (CA)-functionalized organophosphonate monolayers onto Al2O3-supported Pd nanoparticle catalysts to prepare bifunctional catalysts containing both Bronsted acid and metal sites. Modification with phosphonic acids (PAs) improved activity and selectivity for gas-phase DO reactions, but the degree of improvement was highly sensitive to both the presence and positioning of the CA group, suggesting a significant contribution from both the PA and CA sites. Short spacer lengths of 1-2 methylene groups between the phosphonate head and CA tail were found to yield the best DO rates and selectivities, whereas longer chains performed similarly to self-assembled monolayers having alkyl tails. Results from a combination of density functional theory and Fourier transform infrared spectroscopy suggested that the enhanced catalyst performance on the optimally positioned CAs was due to the generation of strong acid sites onmore »
- Authors:
-
- Univ. of Colorado, Boulder, CO (United States)
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Publication Date:
- Research Org.:
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- OSTI Identifier:
- 1433482
- Report Number(s):
- NREL/JA-5100-71319
Journal ID: ISSN 1932-7447; TRN: US1802537
- Grant/Contract Number:
- AC36-08GO28308
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Physical Chemistry. C
- Additional Journal Information:
- Journal Volume: 122; Journal Issue: 12; Journal ID: ISSN 1932-7447
- Publisher:
- American Chemical Society
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; bi-functional catalysts; catalyst performance; catalytic chemistry; cyclic structures; improved activities; methylene groups; organic monolayers
Citation Formats
Coan, Patrick D., Ellis, Lucas D., Griffin, Michael B., Schwartz, Daniel K., and Medlin, J. Will. Enhancing Cooperativity in Bifunctional Acid–Pd Catalysts with Carboxylic Acid-Functionalized Organic Monolayers. United States: N. p., 2018.
Web. doi:10.1021/acs.jpcc.7b12442.
Coan, Patrick D., Ellis, Lucas D., Griffin, Michael B., Schwartz, Daniel K., & Medlin, J. Will. Enhancing Cooperativity in Bifunctional Acid–Pd Catalysts with Carboxylic Acid-Functionalized Organic Monolayers. United States. https://doi.org/10.1021/acs.jpcc.7b12442
Coan, Patrick D., Ellis, Lucas D., Griffin, Michael B., Schwartz, Daniel K., and Medlin, J. Will. Mon .
"Enhancing Cooperativity in Bifunctional Acid–Pd Catalysts with Carboxylic Acid-Functionalized Organic Monolayers". United States. https://doi.org/10.1021/acs.jpcc.7b12442. https://www.osti.gov/servlets/purl/1433482.
@article{osti_1433482,
title = {Enhancing Cooperativity in Bifunctional Acid–Pd Catalysts with Carboxylic Acid-Functionalized Organic Monolayers},
author = {Coan, Patrick D. and Ellis, Lucas D. and Griffin, Michael B. and Schwartz, Daniel K. and Medlin, J. Will},
abstractNote = {Here, cooperative catalysts containing a combination of noble metal hydrogenation sites and Bronsted acid sites are critical for many reactions, including the deoxygenation (DO) of biomass-derived oxygenates in the upgrading of pyrolysis oil. One route toward the design of cooperative catalysts is to tether two different catalytically active functions so that they are in close proximity while avoiding undesirable interactions that can block active sites. Here, we deposited carboxylic acid (CA)-functionalized organophosphonate monolayers onto Al2O3-supported Pd nanoparticle catalysts to prepare bifunctional catalysts containing both Bronsted acid and metal sites. Modification with phosphonic acids (PAs) improved activity and selectivity for gas-phase DO reactions, but the degree of improvement was highly sensitive to both the presence and positioning of the CA group, suggesting a significant contribution from both the PA and CA sites. Short spacer lengths of 1-2 methylene groups between the phosphonate head and CA tail were found to yield the best DO rates and selectivities, whereas longer chains performed similarly to self-assembled monolayers having alkyl tails. Results from a combination of density functional theory and Fourier transform infrared spectroscopy suggested that the enhanced catalyst performance on the optimally positioned CAs was due to the generation of strong acid sites on the Al2O3 support adjacent to the metal. Furthermore, the high activity of these sites was found to result from a hydrogen-bonded cyclic structure involving cooperativity between the phosphonate head group and CA tail function. More broadly, these results indicate that functional groups tethered to supports via organic ligands can influence catalytic chemistry on metal nanoparticles.},
doi = {10.1021/acs.jpcc.7b12442},
journal = {Journal of Physical Chemistry. C},
number = 12,
volume = 122,
place = {United States},
year = {2018},
month = {3}
}
Web of Science
Figures / Tables:

Works referenced in this record:
The critical role of water at the gold-titania interface in catalytic CO oxidation
journal, September 2014
- Saavedra, J.; Doan, H. A.; Pursell, C. J.
- Science, Vol. 345, Issue 6204
Reactivity of the Gold/Water Interface During Selective Oxidation Catalysis
journal, September 2010
- Zope, B. N.; Hibbitts, D. D.; Neurock, M.
- Science, Vol. 330, Issue 6000
Introducing structural sensitivity into adsorption–energy scaling relations by means of coordination numbers
journal, April 2015
- Calle-Vallejo, Federico; Loffreda, David; Koper, Marc T. M.
- Nature Chemistry, Vol. 7, Issue 5
Trimethylsilyl functionalization of alumina (γ-Al 2 O 3 ) increases activity for 1,2-propanediol dehydration
journal, January 2016
- Ellis, L. D.; Pylypenko, S.; Ayotte, S. R.
- Catalysis Science & Technology, Vol. 6, Issue 14
Density‐functional thermochemistry. III. The role of exact exchange
journal, April 1993
- Becke, Axel D.
- The Journal of Chemical Physics, Vol. 98, Issue 7, p. 5648-5652
Ab Initio Calculation of Vibrational Absorption and Circular Dichroism Spectra Using Density Functional Force Fields
journal, November 1994
- Stephens, P. J.; Devlin, F. J.; Chabalowski, C. F.
- The Journal of Physical Chemistry, Vol. 98, Issue 45, p. 11623-11627
Formation and Structure of Self-Assembled Monolayers
journal, January 1996
- Ulman, Abraham
- Chemical Reviews, Vol. 96, Issue 4, p. 1533-1554
Molecular dynamics simulations of phosphonic acid–aluminum oxide self-organization and their evolution into ordered monolayers
journal, January 2017
- Dietrich, H.; Schmaltz, T.; Halik, M.
- Physical Chemistry Chemical Physics, Vol. 19, Issue 7
An evaluation of the performance of density functional theory, MP2, MP4, F4, G2(MP2) and G2 procedures in predicting gas-phase proton affinities
journal, December 1994
- Smith, Brian J.; Radom, Leo
- Chemical Physics Letters, Vol. 231, Issue 4-6
Gas-phase acidities: a comparison of density functional, MP2, MP4, F4, G2(MP2, SVP), G2(MP2) and G2 procedures
journal, October 1995
- Smith, Brian J.; Radom, Leo
- Chemical Physics Letters, Vol. 245, Issue 1
Intramolecular Hydrogen Bonding as a Factor in Determining the K1/K2 Ratios of Dicarboxylic Acids.
journal, January 1963
- Eberson, Lennart; Wadsö, Ingemar; Lindberg, Bengt
- Acta Chemica Scandinavica, Vol. 17
The Geometry of Intramolecular Hydrogen Bonding in 1,2-Dicarboxylic Acids
journal, March 1967
- McCoy, Layton L.
- Journal of the American Chemical Society, Vol. 89, Issue 7
Intramolecular hydrogen bonding in monoanions of o-phthalic acid and the homologous oxalic acid series in acetonitrile
journal, March 1975
- Kolthoff, I. M.; Chantooni, M. K.
- Journal of the American Chemical Society, Vol. 97, Issue 6
Investigation of vinyl phosphonic acid/hydroxylated α-Al2O3() reaction enthalpies
journal, November 2001
- Hector Jr, L. G.; Opalka, S. M.; Nitowski, G. A.
- Surface Science, Vol. 494, Issue 1
Infrared Spectra of Alkylphosphonic Acid Bound to Aluminium Surfaces
journal, August 2007
- Luschtinetz, Regina; Seifert, Gotthard; Jaehne, Evelin
- Macromolecular Symposia, Vol. 254, Issue 1
Works referencing / citing this record:
Role of tungsten modifiers in bimetallic catalysts for enhanced hydrodeoxygenation activity and selectivity
journal, January 2020
- Rasmussen, Mathew J.; Medlin, J. Will
- Catalysis Science & Technology, Vol. 10, Issue 2
Figures / Tables found in this record: