It remains difficult to understand the surface of solid acid catalysts at the molecular level, despite their importance for industrial catalytic applications. A sulfated zirconium-based metal–organic framework, MOF-808-SO4, was previously shown to be a strong solid Brønsted acid material. In this report, we probe the origin of its acidity through an array of spectroscopic, crystallographic and computational characterization techniques. The strongest Brønsted acid site is shown to consist of a specific arrangement of adsorbed water and sulfate moieties on the zirconium clusters. When a water molecule adsorbs to one zirconium atom, it participates in a hydrogen bond with a sulfate moiety that is chelated to a neighbouring zirconium atom; this motif, in turn, results in the presence of a strongly acidic proton. On dehydration, the material loses its acidity. The hydrated sulfated MOF exhibits a good catalytic performance for the dimerization of isobutene (2-methyl-1-propene), and achieves a 100% selectivity for C8 products with a good conversion efficiency.
Subscribe to Journal
Get full journal access for 1 year
only $13.33 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Synthetic and experimental procedures, as well as crystallographic, spectroscopic and computational data are provided in the Supplementary Information. Crystallographic data for the structures reported in this Article have been deposited at the Cambridge Crystallographic Data Centre, under deposition numbers CCDC 1871192 (MOF-808), 1871193 (MOF-808-SO4) and 1871194 (MOF-808-SeO4). Copies of the data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif. All other data supporting the findings of this study are available within the article and its Supplementary Information, or from the corresponding author upon reasonable request.
Arata, K. Solid superacids. Adv. Catal. 37, 165 (1990).
Ward, D. A. & Ko, E. I. One-step synthesis and characterization of zirconia–sulfate aerogels as solid superacids. J. Catal. 150, 18–33 (1994).
Haase, F. & Sauer, J. The surface structure of sulfated zirconia: periodic ab initio study of sulfuric acid adsorbed on ZrO2(101) and ZrO2(001). J. Am. Chem. Soc. 120, 13503–13512 (1998).
Bensitel, M., Saur, O., Lavalley, J. C. & Morrow, B. A. An infrared study of sulfated zirconia. Mater. Chem. Phys. 19, 147–156 (1988).
Clearfield, A., Serrette, G. P. D. & Khazi-Syed, A. H. Nature of hydrous zirconia and sulfated hydrous zirconia. Catal. Today 20, 295–312 (1994).
Kustov, L. M., Kazansky, V. B., Figueras, F. & Tichit, D. Investigation of the acidic properties of ZrO2 modified by SO4 2− anions. J. Catal. 150, 143–149 (1994).
Adeeva, V. et al. Acid sites in sulfated and metal-promoted zirconium dioxide catalysts. J. Catal. 151, 364–372 (1995).
Bolis, V., Magnacca, G., Cerrato, G. & Morterra, C. Microcalorimetric characterization of structural and chemical heterogeneity of superacid SO4/ZrO2 systems. Langmuir 13, 888–894 (1997).
Hino, M., Kurashige, M., Matsuhashi, H. & Arata, K. The surface structure of sulfated zirconia: studies of XPS and thermal analysis. Thermochim. Acta 441, 35–41 (2006).
Arata, K. Organic syntheses catalyzed by superacidic metal oxides: sulfated zirconia and related compounds. Green Chem. 11, 1719–1728 (2009).
Yadav, G. D. & Nair, J. J. Sulfated zirconia and its modified versions as promising catalysts for industrial processes. Microporous Mesoporous Mater. 33, 1–48 (1999).
Jiang, J. et al. Superacidity in sulfated metal—organic framework-808. J. Am. Chem. Soc. 136, 12844–12847 (2014).
Furukawa, H. et al. Water adsorption in porous metal–organic frameworks and related materials. J. Am. Chem. Soc. 136, 4369–4381 (2014).
Goesten, M. G. et al. Sulfation of metal–organic frameworks: opportunities for acid catalysis and proton conductivity. J. Catal. 281, 177–187 (2011).
Osborn Popp, T. M. & Yaghi, O. M. Sequence-dependent materials. Acc. Chem. Res. 50, 532–534 (2017).
Cairns, A. B. & Goodwin, A. L. Structural disorder in molecular framework materials. Chem. Soc. Rev. 42, 4881–4893 (2013).
Furukawa, H., Müller, U. & Yaghi, O. M. 'Heterogeneity within order' in metal–organic frameworks. Angew. Chem. Int. Ed. 54, 3417–3430 (2015).
Trickett, C. A. et al. Definitive molecular level characterization of defects in UiO-66 crystals. Angew. Chem. Int. Ed. 54, 11162–11167 (2015).
Åberg, M. & Glaser, J. 17O and 1H NMR study of the tetranuclear hydroxo zirconium complex in aqueous solution. Inorg. Chim. Acta 206, 53–61 (1993).
Springborg, J. Hydroxo-bridged complexes of chromium (iii), cobalt (iii), rhodium (iii), and iridium (iii). Adv. Inorg. Chem. 32, 55–169 (1988).
Hall, J. Lab Manual for Zumdahl/Zumdahl’s Chemistry 656 (Brooks Cole, Pacific Grove, 2002).
Zheng, A., Zhang, H., Lu, X., Liu, S. B. & Deng, F. Theoretical predictions of 31P NMR chemical shift threshold of trimethylphosphine oxide absorbed on solid acid catalysts. J. Phys. Chem. B 112, 4496–4505 (2008).
Zheng, A. et al. 31P chemical shift of adsorbed trialkylphosphine oxides for acidity characterization of solid acids catalysts. J. Phys. Chem. 112, 7349–7356 (2008).
Zheng, A., Huang, S. J., Liu, S. B. & Deng, F. Acid properties of solid acid catalysts characterized by solid-state 31P NMR of adsorbed phosphorous probe molecules. Phys. Chem. Chem. Phys. 13, 14889 (2011).
Chen, W. H. et al. A solid-state NMR, FT-IR and TPD study on acid properties of sulfated and metal-promoted zirconia: influence of promoter and sulfation treatment. Catal. Today 116, 111–120 (2006).
Lunsford, J. H., Sang, H., Campbell, S. M., Liang, C. H. & Anthony, R. G. An NMR study of acid sites on sulfated-zirconia catalysts using trimethylphosphine as a probe. Catal. Lett. 27, 305–314 (1994).
Gottwald, J., Demco, D. E., Graf, R. & Spiess, H. W. High-resolution double-quantum NMR spectroscopy of homonuclear spin pairs and proton connectivities in solids. Chem. Phys. Lett. 243, 314–323 (1995).
Schnell, I., Brown, S. P., Low, H. Y., Ishida, H. & Spiess, H. W. An investigation of hydrogen bonding in benzoxazine dimers by fast magic-angle spinning and double-quantum 1H NMR spectroscopy. J. Am. Chem. Soc. 120, 11784–11795 (1998).
Mahdi, H. I. & Muraza, O. Conversion of isobutylene to octane-booster compounds after methyl tert-butyl ether phaseout: the role of heterogeneous catalysis. Ind. Eng. Chem. Res. 55, 11193–11210 (2016).
Takahashi, K., Yamashita, M. & Nozaki, K. Tandem hydroformylation/hydrogenation of alkenes to normal alcohols using Rh/Ru dual catalyst or Ru single component catalyst. J. Am. Chem. Soc. 134, 18746–18757 (2012).
Behr, A. Ullman’s Encyclopedia of Industrial Chemistry 223–269 (Wiley, Hoboken, 2010).
Izquierdo, J. F., Vila, M., Tejero, J., Cunill, F. & Iborra, M. Kinetic study of isobutene dimerization catalyzed by a macroporous sulphonic acid resin. Appl. Catal. A 106, 155–165 (1993).
Kamath, R. S., Qi, Z., Sundmacher, K., Aghalayam, P. & Mahajani, S. M. Process analysis for dimerization of isobutene by reactive distillation. Ind. Eng. Chem. Res. 45, 1575–1582 (2006).
Song, X. & Sayari, A. Sulfated zirconia-based strong solid-acid catalysts: recent progress. Cat. Rev. 38, 329–412 (1996).
Himmel, D., Goll, S. K., Leito, I. & Krossing, I. A unified pH scale for all phases. Angew. Chem. Int. Ed. 49, 6885–6888 (2010).
Viggiano, A. A., Henchman, M. J., Dale, F., Deakyne, C. A. & Paulson, J. F. Gas-phase reactions of weak Brønsted bases I–, PO3 –, HSO4 –, FSO3 –, and CF3SO3 – with strong Brønsted acids H2SO4, FSO3H, and CF3SO3H, a quantitative intrinsic superacidity scale for the sulfonic acids XSO3H (X = HO, F, and CF3). J. Am. Chem. Soc. 114, 4299–4306 (1992).
This work, including the synthesis, characterization and crystal structure analysis, was funded by BASF SE and the US Department of Defense, Defense Threat Reduction Agency (HDTRA 1-12-1-0053). Work performed at the Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under Contract no. DE-AC02-05CH11231. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. NMR work was supported as part of the Center for Gas Separations Relevant to Clean Energy Technologies, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Basic Energy Sciences under Award no. DE-SC0001015. T.M.O.P. acknowledges funding from the NSF Graduate Research Fellowship Program. C.Y. acknowledges support from a Hewlett-Packard Stanford Graduate Fellowship. P.U. acknowledges the German Research Foundation (DFG, PU 286/1-1). M.J.K. is grateful for financial support through the German Research Foundation (DFG, KA 4484/1-1). We acknowledge B. Rungtaweevoranit for his assistance with electron microscopy, and S. Teat and L. McCormick for the synchrotron X-ray diffraction data acquisition support at beamline 11.3.1 of the Advanced Light Source, Lawrence Berkeley National Laboratory.
The authors declare no competing interests.
Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Synthetic and experimental procedures; Crystallographic, spectroscopic and computational data; Supplementary Figures 1–30; Supplementary Tables 1–7; Supplementary References 1–14
CIF for MOF-808; CCDC reference: 1871192
Structure-factor file for MOF-808; CCDC: reference 1871192
CIF for MOF-808-SO4; CCDC reference: 1871193
Structure-factor file for MOF-808-SO4; CCDC reference: 1871193
CIF for MOF-808-SeO4; CCDC reference: 1871194
Structure-factor file for MOF-808-SeO4; CCDC reference: 1871194
About this article
Cite this article
Trickett, C.A., Osborn Popp, T.M., Su, J. et al. Identification of the strong Brønsted acid site in a metal–organic framework solid acid catalyst. Nature Chem 11, 170–176 (2019). https://doi.org/10.1038/s41557-018-0171-z
Alterations to secondary building units of metal–organic frameworks for the development of new functions
Inorganic Chemistry Frontiers (2020)
Inorganica Chimica Acta (2020)
Spectroscopically Resolved Binding Sites for the Adsorption of Sarin Gas in a Metal–Organic Framework: Insights beyond Lewis Acidity
The Journal of Physical Chemistry Letters (2019)
Efficient Production of Ethyl Levulinate from Furfuryl Alcohol Catalyzed by Modified Zirconium Phosphate
Journal of Applied Crystallography (2019)