Identifying Sn Site Heterogeneities Prevalent Among Sn-Beta Zeolites

Helvetica Chimica Acta

Volumn 99, Issue 12, 2016, Pages 916-927

  Wolf, Patrick ^a,b   Liao, Wei Chih ^a   Ong, Ta Chung ^a   Valla, Maxence ^a   Harris, James W ^c   Gounder, Rajamani ^c   van der Graaff, William N P ^d   Pidko, Evgeny A ^d   Hensen, Emiel J M ^d   Ferrini, Paola ^e   Dijkmans, Jan ^e   Sels, Bert ^e   Hermans, Ive ^b   Copéret, Christophe ^a  

^a ETH ZURICH   (Switzerland)

^b University of Wisconsin Madison   (United States)

^c PURDUE UNIVERSITY   (United States)

^d EINDHOVEN UNIVERSITY OF TECHNOLOGY   (Netherlands)

^e UNIVERSITY OF LEUVEN   (Belgium)

Author keywords

119Sn NMR; DNP NMR; Lewis acid; Sn Beta; Zeolites

Indexed keywords

CATALYSIS; FLUORINE COMPOUNDS; HYDROTHERMAL SYNTHESIS; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; ZEOLITES;

119SN NMR; CATALYTIC REACTIONS; DNP NMR; HYDROTHERMALLY SYNTHESIZED; LEWIS ACID; SN-BETA; SYNTHESIS PARAMETERS; SYNTHESIS PROCEDURE;

TIN COMPOUNDS;

FLUORIDE; TIN BETA ZEOLITE; TIN DERIVATIVE; UNCLASSIFIED DRUG; ZEOLITE;

ARTICLE; CATALYSIS; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; POLARIZATION; PRIORITY JOURNAL; SAMPLE; SYNTHESIS;

EID: 85000613217     PISSN: 0018019X     EISSN: 15222675     Source Type: Journal    
DOI: 10.1002/hlca.201600234     Document Type: Article

References (83)

1. M. Moliner, ‘State of the art of Lewis acid-containing zeolites: lessons from fine chemistry to new biomass transformation processes’, Dalton Trans. 2014, 43, 4197 – 4208.
2. H. Y. Luo, J. D. Lewis, Y. Román-Leshkov, ‘Lewis Acid Zeolites for Biomass Conversion: Persepectives and Challenges on Reactivity, Synthesis, and Stability’, Annu. Rev. Chem., Biomol. Eng. 2016, 7, 663 – 692.
3. A. Corma, L. T. Nemeth, M. Renz, S. Valencia, ‘Sn-zeolite beta as a heterogeneous chemoselective catalyst for Baeyer–Villiger oxidations’, Nature 2001, 412, 423 – 425.
4. A. Corma, V. Fornés, S. Iborra, M. Mifsud, M. Renz, ‘One-pot synthesis of phenols from aromatic aldehydes by Baeyer-Villiger oxidation with H2O2 using water-tolerant Lewis acids in molecular sieves’, J. Catal. 2004, 221, 67 – 76.
5. Y. Román-Leshkov, M. E. Davis, ‘Activation of Carbonyl-Containing Molecules with Solid Lewis Acids in Aqueous Media’, ACS Catal. 2011, 1, 1566 – 1580.
6. A. Corma, M. E. Domine, S. Valencia, ‘Water-resistant solid Lewis acid catalysts: Meerwein–Ponndorf–Verley and Oppenauer reactions catalyzed by tin-beta zeolite’, J. Catal. 2003, 215, 294 – 304.
7. L. Bui, H. Luo, W. R. Gunther, Y. Román-Leshkov, ‘Domino Reaction Catalyzed by Zeolites with Brønsted and Lewis Acid Sites for the Production of γ-Valerolactone from Furfural’, Angew. Chem., Int. Ed. 2013, 52, 8022 – 8025.
8. A. Corma, M. Renz, ‘Sn-Beta zeolite as diastereoselective water-resistant heterogeneous Lewis-acid catalyst for carbon-carbon bond formation in the intramolecular carbonyl–ene reaction’, Chem. Commun. 2004, 550 – 551.
9. J. J. Pacheco, M. E. Davis, ‘Synthesis of terephthalic acid via Diels-Alder reactions with ethylene and oxidized variants of 5-hydroxymethylfurfural’, Proc. Natl. Acad. Sci. U.S.A. 2014, 111, 8363 – 8367.
10. S. Van de Vyver, Y. Román-Leshkov, ‘Metalloenzyme-Like Zeolites as Lewis Acid Catalysts for C-C Bond Formation’, Angew. Chem., Int. Ed. 2015, 54, 12554 – 12561.
11. M. S. Holm, Y. J. Pagán-Torres, S. Saravanamurugan, A. Riisager, J. A. Dumesic, E. Taarning, ‘Sn-Beta catalysed conversion of hemicellulosic sugars’, Green Chem. 2012, 14, 702 – 706.
12. E. Taarning, S. Saravanamurugan, M. Spangsberg Holm, J. Xiong, R. M. West, C. H. Christensen, ‘Zeolite-Catalyzed Isomerization of Triose Sugars’, ChemSusChem 2009, 2, 625 – 627.
13. M. Moliner, Y. Román-Leshkov, M. E. Davis, ‘Tin-containing zeolites are highly active catalysts for the isomerization of glucose in water’, Proc. Natl. Acad. Sci. U.S.A. 2010, 107, 6164 – 6168.
14. V. Choudhary, A. B. Pinar, S. I. Sandler, D. G. Vlachos, R. F. Lobo, ‘Xylose Isomerization to Xylulose and its Dehydration to Furfural in Aqueous Media’, ACS Catal. 2011, 1, 1724 – 1728.
15. R. Bermejo-Deval, R. Gounder, M. E. Davis, ‘Framework and Extraframework Tin Sites in Zeolite Beta React Glucose Differently’, ACS Catal. 2012, 2, 2705 – 2713.
16. W. R. Gunther, Y. Wang, Y. Ji, V. K. Michaelis, S. T. Hunt, R. G. Griffin, Y. Román-Leshkov, ‘Sn-Beta zeolites with borate salts catalyse the epimerization of carbohydrates via an intramolecular carbon shift’, Nat. Commun. 2012, 3, Art.-No. 1109.
17. J. D. Lewis, S. Van de Vyver, A. J. Crisci, W. R. Gunther, V. K. Michaelis, R. G. Griffin, Y. Román-Leshkov, ‘A Continuous Flow Strategy for the Coupled Transfer Hydrogenation and Etherification of 5-(Hydroxymethyl)furfural using Lewis Acid Zeolites’, ChemSusChem 2014, 7, 2255 – 2265.
18. B. Tang, W. Dai, G. Wu, N. Guan, L. Li, M. Hunger, ‘Improved Postsynthesis Strategy to Sn-Beta Zeolites as Lewis Acid Catalysts for the Ring-Opening Hydration of Epoxides’, ACS Catal. 2014, 4, 2801 – 2810.
19. C. M. Osmundsen, M. S. Holm, S. Dahl, E. Taarning, ‘Tin-containing silicates: structure-activity relations’, Proc. Royal Soc. A 2012, 468, 2000 – 2016.
20. J. Dijkmans, M. Dusselier, D. Gabriëls, K. Houthoofd, P. C. M. M. Magusin, S. Huang, Y. Pontikes, M. Trekels, A. Vantomme, L. Giebeler, S. Oswald, B. F. Sels, ‘Cooperative Catalysis for Multistep Biomass Conversion with Sn/Al Beta Zeolite’, ACS Catal. 2015, 5, 928 – 940.
21. R. De Clercq, M. Dusselier, C. Christiaens, J. Dijkmans, R. I. Iacobescu, Y. Pontikes, B. F. Sels, ‘Confinement Effects in Lewis Acid-Catalyzed Sugar Conversion: Steering Toward Functional Polyester Building Blocks’, ACS Catal. 2015, 5, 5803 – 5811.
22. S. V. Valencia, A. C. Canos, US Pat. US000006306364B1, 1999.
23. P. Li, G. Liu, H. Wu, Y. Liu, J.-G. Jiang, P. Wu, ‘Postsynthesis and Selective Oxidation Properties of Nanosized Sn-Beta Zeolite’, J. Phys. Chem. C 2011, 115, 3663 – 3670.
24. J. Dijkmans, D. Gabriëls, M. Dusselier, de Clippel F., P. Vanelderen, K. Houthoofd, A. Malfliet, Y. Pontikes, B. F. Sels, ‘Productive sugar isomerization with highly active Sn in dealuminated β zeolites’, Green Chem. 2013, 15, 2777 – 2785.
25. W. N. P. van der Graaff, G. Li, B. Mezari, E. A. Pidko, E. J. M. Hensen, ‘Synthesis of Sn-Beta with Exclusive and High Framework Sn Content’, ChemCatChem 2015, 7, 1152 – 1160.
26. J. Dijkmans, J. Demol, K. Houthoofd, S. Huang, Y. Pontikes, B. Sels, ‘Post-synthesis Snβ: An exploration of synthesis parameters and catalysis’, J. Catal. 2015, 330, 545 – 557.
27. C. Hammond, S. Conrad, I. Hermans, ‘Simple and Scalable Preparation of Highly Active Lewis Acidic Sn-β’, Angew. Chem., Int. Ed. 2012, 51, 11736 – 11739.
28. C. Hammond, D. Padovan, A. Al-Nayili, P. P. Wells, E. K. Gibson, N. Dimitratos, ‘Identification of Active and Spectator Sn Sites in Sn-β Following Solid-State Stannation, and Consequences for Lewis Acid Catalysis’, ChemCatChem 2015, 7, 3322 – 3331.
29. C.-C. Chang, Z. Wang, P. Dornath, H. J. Cho, W. Fan, ‘Rapid synthesis of Sn-Beta for the isomerization of cellulosic sugars’, RSC Adv. 2012, 2, 10475 – 10477.
30. C.-C. Chang, H. J. Cho, Z. Wang, X. Wang, W. Fan, ‘Fluoride-free synthesis of a Sn-BEA catalyst by dry gel conversion’, Green Chem. 2015, 17, 2943 – 2951.
31. J. W. Harris, M. J. Cordon, J. R. Di Iorio, J. C. Vega-Vila, F. H. Ribeiro, R. Gounder, ‘Titration and quantification of open and closed Lewis acid sites in Sn-Beta zeolites that catalyze glucose isomerization’, J. Catal. 2016, 335, 141 – 154.
32. P. Wolf, M. Valla, F. Núñez-Zarur, A. Comas-Vives, A. J. Rossini, C. Firth, H. Kallas, A. Lesage, L. Emsley, C. Copéret, I. Hermans, ‘Correlating Synthetic Methods, Morphology, Atomic-Level Structure, and Catalytic Activity of Sn-β Catalysts’, ACS Catal. 2016, 6, 4047 – 4063.
33. J. Dijkmans, M. Dusselier, W. Janssens, M. Trekels, A. Vantomme, E. Breynaert, C. Kirschhock, B. F. Sels, ‘An Inner-/Outer-Sphere Stabilized Sn Active Site in β-Zeolite: Spectroscopic Evidence and Kinetic Consequences’, ACS Catal. 2016, 6, 31 – 46.
34. R. Gounder, M. E. Davis, ‘Monosaccharide and disaccharide isomerization over Lewis acid sites in hydrophobic and hydrophilic molecular sieves’, J. Catal. 2013, 308, 176 – 188.
35. R. Gounder, ‘Hydrophobic microporous and mesoporous oxides as Brønsted and Lewis acid catalysts for biomass conversion in liquid water’, Catal. Sci. Technol. 2014, 4, 2877 – 2886.
36. S. Storck, H. Bretinger, W. F. Maier, ‘Characterization of micro- and mesoporous solids by physisorption methods and pore-size analysis’, Appl. Catal. A 1998, 174, 137 – 146.
37. C. Baerlocher, L. B. McCusker, D. H. Olson, International Zeolite Association Structure Commission, ‘Atlas of zeolite framework types dedicated to Walter M. Meier’, 6th rev. Edn., Elsevier, Amsterdam, 2007.
38. M. Thommes, S. Mitchell, J. Pérez-Ramírez, ‘Surface and Pore Structure Assessment of Hierarchical MFI Zeolites by Advanced Water and Argon Sorption Studies’, J. Phys. Chem. C 2012, 116, 18816 – 18823.
39. R. Bermejo-Deval, R. S. Assary, E. Nikolla, M. Moliner, Y. Román-Leshkov, S.-J. Hwang, A. Palsdottir, D. Silverman, R. F. Lobo, L. A. Curtiss, M. E. Davis, ‘Metalloenzyme-like catalyzed isomerizations of sugars by Lewis acid zeolites’, Proc. Natl Acad. Sci. U.S.A. 2012, 109, 9727 – 9732.
40. S. Tolborg, A. Katerinopoulou, D. D. Falcone, I. Sádaba, C. M. Osmundsen, R. J. Davis, E. Taarning, P. Fristrup, M. S. Holm, ‘Incorporation of tin affects crystallization, morphology, and crystal composition of Sn-Beta’, J. Mater. Chem. A 2014, 2, 20252 – 20262.
41. M. Boronat, P. Concepción, A. Corma, M. Renz, S. Valencia, ‘Determination of the catalytically active oxidation Lewis acid sites in Sn-beta zeolites, and their optimisation by the combination of theoretical and experimental studies’, J. Catal. 2005, 234, 111 – 118.
42. P. Wolf, M. Valla, A. J. Rossini, A. Comas-Vives, F. Núñez-Zarur, B. Malaman, A. Lesage, L. Emsley, C. Copéret, I. Hermans, ‘NMR Signatures of the Active Sites in Sn-β Zeolite’, Angew. Chem., Int. Ed. 2014, 53, 10179 – 10183.
43. R. Bermejo-Deval, M. Orazov, R. Gounder, S.-J. Hwang, M. E. Davis, ‘Active Sites in Sn-Beta for Glucose Isomerization to Fructose and Epimerization to Mannose’, ACS Catal. 2014, 4, 2288 – 2297.
44. M. Boronat, A. Corma, M. Renz, ‘Mechanism of the Meerwein–Ponndorf–Verley–Oppenauer (MPVO) redox equilibrium on Sn- and Zr-beta zeolite catalysts’, J. Phys. Chem. B 2006, 110, 21168 – 21174.
45. H. Y. Luo, D. F. Consoli, W. R. Gunther, Y. Román-Leshkov, ‘Investigation of the reaction kinetics of isolated Lewis acid sites in Beta zeolites for the Meerwein–Ponndorf–Verley reduction of methyl levulinate to γ-valerolactone’, J. Catal. 2014, 320, 198 – 207.
46. B. D. Montejo-Valencia, M. C. Curet-Arana, ‘DFT Study of the Lewis Acidities and Relative Hydrothermal Stabilities of BEC and BEA Zeolites Substituted with Ti, Sn, and Ge’, J. Phys. Chem. C 2015, 119, 4148 – 4157.
47. N. K. Mal, A. V. Ramaswamy, ‘Hydroxylation of phenol over Sn-silicalite-1 molecular sieve: Solvent effects’, J. Mol. Catal. A 1996, 105, 149 – 158.
48. G. Pang, S. Chen, Y. Koltypin, A. Zaban, S. Feng, A. Gedanken, ‘Controlling the particle size of calcined SnO2nanocrystals’, Nano Lett. 2001, 1, 723 – 726.
49. N. Chiodini, A. Paleari, D. DiMartino, G. Spinolo, ‘SnO2nanocrystals in SiO2: A wide-band-gap quantum-dot system’, Appl Phys Lett 2002, 81, 1702 – 1704.
50. M. Bhagwat, P. Shah, V. Ramaswamy, ‘Synthesis of nanocrystalline SnO2 powder by amorphous citrate route’, Mater. Lett. 2003, 57, 1604 – 1611.
51. S. Roy, K. Bakhmutsky, E. Mahmoud, R. F. Lobo, R. J. Gorte, ‘Probing Lewis Acid Sites in Sn-Beta Zeolite’, ACS Catal. 2013, 3, 573 – 580.
52. S. R. Bare, S. D. Kelly, W. Sinkler, J. J. Low, F. S. Modica, S. Valencia, A. Corma, L. T. Nemeth, ‘Uniform Catalytic Site in Sn-β-Zeolite Determined Using X-ray Absorption Fine Structure’, J. Am. Chem. Soc. 2005, 127, 12924 – 12932.
53. S. Shetty, S. Pal, D. G. Kanhere, A. Goursot, ‘Structural, Electronic, and Bonding Properties of Zeolite Sn-Beta: A Periodic Density Functional Theory Study’, Chem. Eur. J. 2006, 12, 518 – 523.
54. G. Yang, E. A. Pidko, E. J. M. Hensen, ‘Structure, Stability, and Lewis Acidity of Mono and Double Ti, Zr, and Sn Framework Substitutions in BEA Zeolites: A Periodic Density Functional Theory Study’, J. Phys. Chem. C 2013, 117, 3976 – 3986.
55. V. Sabarinathan, C. Vinod Chandran, S. Ramasamy, S. Ganapathy, ‘Sn-119 magic angle spinning NMR of nanocrystalline SnO2’, J. Nanosci. Nanotechnol. 2008, 8, 321 – 328.
56. S. Indris, M. Scheuermann, S. M. Becker, V. Šepelák, R. Kruk, J. Suffner, F. Gyger, C. Feldmann, A. S. Ulrich, H. Hahn, ‘Local Structural Disorder and Relaxation in SnO2Nanostructures Studied by 119Sn MAS NMR and 119Sn Mössbauer Spectroscopy’, J. Phys. Chem. C 2011, 115, 6433 – 6437.
57. S.-J. Hwang, R. Gounder, Y. Bhawe, M. Orazov, R. Bermejo-Deval, M. E. Davis, ‘Solid State NMR Characterization of Sn-Beta Zeolites that Catalyze Glucose Isomerization and Epimerization’, Top. Catal. 2015, 58, 435 – 440.
58. Y. G. Kolyagin, A. V. Yakimov, S. Tolborg, P. N. R. Vennestrøm, I. I. Ivanova, ‘Application of 119Sn CPMG MAS NMR for Fast Characterization of Sn Sites in Zeolites with Natural 119Sn Isotope Abundance’, J. Phys. Chem. Lett. 2016, 7, 1249 – 1253.
59. W. R. Gunther, V. K. Michaelis, M. A. Caporini, R. G. Griffin, Y. Román-Leshkov, ‘Dynamic Nuclear Polarization NMR Enables the Analysis of Sn-Beta Zeolite Prepared with Natural Abundance119Sn Precursors’, J. Am. Chem. Soc. 2014, 136, 6219 – 6222.
60. S. Mintova, V. Valtchev, T. Onfroy, C. Marichal, H. Knözinger, T. Bein, ‘Variation of the Si/Al ratio in nanosized zeolite Beta crystals’, Microporous Mesoporous Mater. 2006, 90, 237 – 245.
61. P. Wolf, C. Hammond, S. Conrad, I. Hermans, ‘Post-synthetic preparation of Sn-, Ti- and Zr-beta: a facile route to water tolerant, highly active Lewis acidic zeolites’, Dalton Trans. 2014, 43, 4514 – 4519.
62. N. M. Loening, M. Rosay, V. Weis, R. G. Griffin, ‘Solution-State Dynamic Nuclear Polarization at High Magnetic Field’, J. Am. Chem. Soc. 2002, 124, 8808 – 8809.
63. T. Maly, G. T. Debelouchina, V. S. Bajaj, K.-N. Hu, C.-G. Joo, M. L. Mak-Jurkauskas, J. R. Sirigiri, P. C. A. van der Wel, J. Herzfeld, R. J. Temkin, R. G. Griffin, ‘Dynamic nuclear polarization at high magnetic fields’, J. Chem. Phys. 2008, 128, 052211.
64. A. Lesage, M. Lelli, D. Gajan, M. A. Caporini, V. Vitzthum, P. Miéville, J. Alauzun, A. Roussey, C. Thieuleux, A. Mehdi, G. Bodenhausen, C. Coperet, L. Emsley, ‘Surface Enhanced NMR Spectroscopy by Dynamic Nuclear Polarization’, J. Am. Chem. Soc. 2010, 132, 15459 – 15461.
65. M. Lelli, D. Gajan, A. Lesage, M. A. Caporini, V. Vitzthum, P. Miéville, F. Héroguel, F. Rascón, A. Roussey, C. Thieuleux, M. Boualleg, L. Veyre, G. Bodenhausen, C. Coperet, L. Emsley, ‘Fast Characterization of Functionalized Silica Materials by Silicon-29 Surface-Enhanced NMR Spectroscopy Using Dynamic Nuclear Polarization’, J. Am. Chem. Soc. 2011, 133, 2104 – 2107.
66. A. J. Rossini, A. Zagdoun, M. Lelli, A. Lesage, C. Copéret, L. Emsley, ‘Dynamic Nuclear Polarization Surface Enhanced NMR Spectroscopy’, Acc. Chem. Res. 2013, 46, 1942 – 1951.
67. Ü. Akbey, W. T. Franks, A. Linden, M. Orwick-Rydmark, S. Lange, H. Oschkinat, ‘Dynamic Nuclear Polarization Enhanced NMR in the Solid-State’, Top. Curr. Chem. 2013, 338, 181 – 228.
68. A. J. Rossini, A. Zagdoun, M. Lelli, J. Canivet, S. Aguado, O. Ouari, P. Tordo, M. Rosay, W. E. Maas, C. Copéret, D. Farrusseng, L. Emsley, A. Lesage, ‘Dynamic Nuclear Polarization Enhanced Solid-State NMR Spectroscopy of Functionalized Metal-Organic Frameworks’, Angew. Chem., Int. Ed. 2012, 51, 123 – 127.
69. T. Kobayashi, F. A. Perras, T. W. Goh, T. L. Metz, W. Huang, M. Pruski, ‘DNP-Enhanced Ultrawideline Solid-State NMR Spectroscopy: Studies of Platinum in Metal-Organic Frameworks’, J. Phys. Chem. Lett. 2016, 7, 2322 – 2327.
70. W. R. Grüning, A. J. Rossini, A. Zagdoun, D. Gajan, A. Lesage, L. Emsley, C. Copéret, ‘Molecular-level characterization of the structure and the surface chemistry of periodic mesoporous organosilicates using DNP-surface enhanced NMR spectroscopy’, Phys. Chem. Chem. Phys. 2013, 15, 13270 – 13274.
71. M. Valla, A. J. Rossini, M. Caillot, C. Chizallet, P. Raybaud, M. Digne, A. Chaumonnot, A. Lesage, L. Emsley, J. A. van Bokhoven, C. Copéret, ‘Atomic Description of the Interface between Silica and Alumina in Aluminosilicates through Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy and First-Principles Calculations’, J. Am. Chem. Soc. 2015, 137, 10710 – 10719.
72. A. R. Mouat, C. George, T. Kobayashi, M. Pruski, R. P. van Duyne, T. J. Marks, P. C. Stair, ‘Highly Dispersed SiOx/Al2O3Catalysts Illuminate the Reactivity of Isolated Silanol Sites’, Angew. Chem., Int. Ed. 2015, 54, 13346 – 13351.
73. L. Piyeteau, T.-C. Ong, A. J. Rossini, L. Emsley, C. Copéret, M. V. Kovalenko, ‘Structure of Colloidal Quantum Dots from Dynamic Nuclear Polarization Surface Enhanced NMR Spectroscopy’, J. Am. Chem. Soc. 2015, 137, 13964 – 13971.
74. A. Zagdoun, A. J. Rossini, D. Gajan, A. Bourdolle, O. Ouari, M. Rosay, W. E. Maas, P. Tordo, M. Lelli, L. Emsley, A. Lesage, C. Copéret, ‘Non-aqueous solvents for DNP surface enhanced NMR spectroscopy’, Chem. Commun. 2012, 48, 654 – 656.
75. A. Zagdoun, G. Casano, O. Ouari, G. Lapadula, A. J. Rossini, M. Lelli, M. Baffert, D. Gajan, L. Veyre, W. E. Maas, M. Rosay, R. T. Weber, C. Thieuleux, C. Coperet, A. Lesage, P. Tordo, L. Emsley, ‘A Slowly Relaxing Rigid Biradical for Efficient Dynamic Nuclear Polarization Surface-Enhanced NMR Spectroscopy: Expeditious Characterization of Functional Group Manipulation in Hybrid Materials’, J. Am. Chem. Soc. 2012, 134, 2284 – 2291.
76. D. J. Kubicki, G. Casano, M. Schwarzwalder, S. Abel, C. Sauvée, K. Ganesan, M. Yulikov, A. J. Rossini, G. Jeschke, C. Coperet, A. Lesage, P. Tordo, O. Ouari, L. Emsley, ‘Rational design of dinitroxide biradicals for efficient cross-effect dynamic nuclear polarization’, Chem. Sci. 2016, 7, 550 – 558.
77. A. Zagdoun, G. Casano, O. Ouari, M. Schwarzwälder, A. J. Rossini, F. Aussenac, M. Yulikov, G. Jeschke, C. Copéret, A. Lesage, P. Tordo, L. Emsley, ‘Large Molecular Weight Nitroxide Biradicals Providing Efficient Dynamic Nuclear Polarization at Temperatures up to 200 K’, J. Am. Chem. Soc. 2013, 135, 12790 – 12797.
78. P. C. A. van der Wel, K.-N. Hu, J. Lewandowski, R. G. Griffin, ‘Dynamic nuclear polarization of amyloidogenic peptide nanocrystals: GNNQQNY, a core segment of the yeast prion protein Sup35p’, J. Am. Chem. Soc. 2006, 128, 10840 – 10846.
79. A. J. Rossini, A. Zagdoun, F. Hegner, M. Schwarzwälder, D. Gajan, C. Copéret, A. Lesage, L. Emsley, ‘Dynamic Nuclear Polarization NMR Spectroscopy of Microcrystalline Solids’, J. Am. Chem. Soc. 2012, 134, 16899 – 16908.
80. O. Lafon, A. S. L. Thankamony, T. Kobayashi, D. Carnevale, V. Vitzthum, I. I. Slowing, K. Kandel, H. Vezin, J. P. Amoureux, G. Bodenhausen, M. Pruski, ‘Mesoporous Silica Nanoparticles Loaded with Surfactant: Low Temperature Magic Angle Spinning 13C and 29Si NMR Enhanced by Dynamic Nuclear Polarization’, J. Phys. Chem. C 2013, 117, 1375 – 1382.
81. A. Pines, M. G. Gibby, J. S. Waugh, ‘Proton-Enhanced NMR of Dilute Spins in Solids’, J. Chem. Phys. 1973, 59, 569 – 590.
82. J. Cejka, ‘Introduction to Zeolite Science and Practice’, Vol. 168, 3rd revised edn, Elsevier, Amsterdam, 2007.
83. A. N. Parvulescu, U. Müller, J. H. Teles, N. Vautravers, G. Uhl, I. Hermans, P. Wolf, C. Hammond, Pat. WO2015067654 A1, 2015.