High-temperature synthesis of finely dispersed oxide materials and C12A7:e electrides in carbon nanoreactor conditions
https://doi.org/10.17586/2220-8054-2018-9-4-558-567
Abstract
Solid-state transformations of the oxide core in core-shell structures Oxide@C consisting of oxide nanoparticles covered with a carbon coating were studied at temperatures of up to 1500 ◦C. It is shown that such coating can stabilize the size of the oxide core nanoparticles for alumina, zirconia, calcium and lanthanum aluminates and act as a shell of a nanoreactor where phase and chemical transformation can take place. For ZrO2@C and Al2O3@C it is demonstrated that it is the preservation of the small particle size that accounts for the preservation of cubic ZrO2 and δ-Al2O3 until the carbothermal reduction temperatures of the corresponding oxides (above 1400 ◦C for Al2O3). The electride state C12A7:e is shown to be formed in C12A7@C material at temperatures above its melting point. The surface of activated C12A7 was found to have a significant concentration of active OH radicals capable of converting diphenylamine into stable nitroxyl radicals.
Supporting agencies: This study was supported by Russian Science Foundation, Project 16-13-10168.
About the Authors
A. M. Volodin
Boreskov Institute of Catalysis
Russian Federation
Russian Federation
Prospekt Lavrentieva, 5, Novosibirsk, 630090
A. F. Bedilo
Boreskov Institute of Catalysis
Russian Federation
Russian Federation
Prospekt Lavrentieva, 5, Novosibirsk, 630090
V. O. Stoyanovskii
Boreskov Institute of Catalysis
Russian Federation
Russian Federation
Prospekt Lavrentieva, 5, Novosibirsk, 630090
V. I. Zaikovskii
Boreskov Institute of Catalysis
Russian Federation
Russian Federation
Prospekt Lavrentieva, 5, Novosibirsk, 630090
References
1. Park J.C., Bang J.U., et al. Ni@SiO2 yolk-shell nanoreactor catalysts: High temperature stability and recyclability. J. Mater. Chem., 2010, 20 (7), P. 1239–1246.
2. Chaudhuri R.G., Paria S. Core/Shell Nanoparticles: Classes, Properties, Synthesis Mechanisms, Characterization, and Applications. Chem. Rev., 2012, 112 (4), P. 2373–2433.
3. Yang W.L., Wang Y.R., et al. Carbon nanocoating: an effective nanoreactor towards well-defined carbon-coated GaN hollow nanospindles. Nanoscale, 2014, 6 (6), P. 3051–3054.
4. Plumejeau S., Alauzun J.G., Boury B. Hybrid metal oxide@biopolymer materials precursors of metal oxides and metal oxide-carbon composites. J. Ceram. Soc. Jpn., 2015, 123 (1441), P. 695–708.
5. Li B., Nam H., et al. Nanoreactor of Nickel-Containing Carbon-Shells as Oxygen Reduction Catalyst. Adv. Mater., 2017, 29 (7), 1605083.
6. Lee J., Kim S.M., Lee I.S. Functionalization of hollow nanoparticles for nanoreactor applications. Nano Today, 2014, 9 (5), P. 631–667.
7. Bedilo A.F., Sigel M.J., et al. Synthesis of carbon-coated MgO nanoparticles. J. Mater. Chem., 2002, 12 (12), P. 3599–3604.
8. Bedilo A.F., Shuvarakova E.I., et al. Effect of Modification with Vanadium or Carbon on Destructive Sorption of Halocarbons over Nanocrystalline MgO: The Role of Active Sites in Initiation of the Solid-State Reaction. J. Phys. Chem. C, 2014, 118 (25), P. 13715– 13725.
9. Yakovlev I.V., Volodin A.M., et al. Stabilizing effect of the carbon shell on phase transformation of the nanocrystalline alumina particles. Ceram. Int., 2018, 44 (5), P. 4801–4806.
10. Volodin A., Bedilo A.F., et al. Nanocrystalline carbon coated alumina with enhanced phase stability at high temperatures. RSC Adv., 2017, 7 (86), P. 54852–54860.
11. Volodin A.M., Zaikovskii V.I., et al. Synthesis of nanocrystalline calcium aluminate C12A7 under carbon nanoreactor conditions. Mater. Lett., 2017, 189, P. 210–212.
12. Volodin A.M., Bedilo A.F., et al. Carbon nanoreactor for the synthesis of nanocrystalline high-temperature oxide materials. Nanotechnologies in Russia, 2014, 9 (11), P. 700–706.
13. Flockhart B.D., Leith I.R., Pink R.C. Evidence for the redox nature of the surface of catalytic aluminas. J. Catal., 1967, 9 (1), P. 45–50.
14. Garcia H., Roth H.D. Generation and reactions of organic radical cations in zeolites. Chem. Rev., 2002, 102 (11), P. 3947–4007.
15. Bedilo A.F., Volodin A.M. Radical cations of aromatic molecules with high ionization potentials on the surfaces of oxide catalysts: Formation, properties, and reactivity. Kinet. Catal., 2009, 50 (2), P. 314–324.
16. Bedilo A.F., Shuvarakova E.I., Rybinskaya A.A., Medvedev D.A. Characterization of Electron-Donor and Electron-Acceptor Sites on the Surface of Sulfated Alumina Using Spin Probes. J. Phys. Chem. C, 2014, 118 (29), P. 15779–15794.
17. Flockhart B.D., Leith I.R., Pink R.C. Electron-transfer at alumina surfaces. Part 3 – Reduction of aromatic nitro-compounds. Trans. Faraday Soc., 1970, 66, P. 469–476.
18. Medvedev D.A., Rybinskaya A.A., et al. Characterization of electron donor sites on Al2O3 surface. Phys. Chem. Chem. Phys., 2012, 14 (8), P. 2587–2598.
19. Shuvarakova E.I., Bedilo A.F., Chesnokov V.V., Kenzhin R.M. Dehydrochlorination of 1-Chlorobutane Over Nanocrystalline MgO: The Role of Electron-Acceptor Sites. Top Catal., 2018, In Press, DOI: 10.1007/s11244-018-1000-8.
20. Khaleel A.A., Klabunde K.J. Characterization of aerogel prepared high-surface-area alumina: In situ FTIR study of dehydroxylation and pyridine adsorption. Chem. Eur. J., 2002, 8 (17), P. 3991–3998.
21. Carnes C.L., Kapoor P.N., Klabunde K.J., Bonevich J. Synthesis, characterization, and adsorption studies of nanocrystalline aluminum oxide and a bimetallic nanocrystalline aluminum oxide/magnesium oxide. Chem. Mater., 2002, 14 (7), P. 2922–2929.
22. Sadykov V., Usoltsev V., et al. Functional nanoceramics for intermediate temperature solid oxide fuel cells and oxygen separation membranes. J. Eur. Ceram. Soc., 2013, 33 (12), P. 2241–2248.
23. Bolshov V.A., Volodin A.M., et al. Radical Intermediates in the Photoinduced Formation of Benzene Cation-Radicals Over H-Zsm-5 Zeolites. J. Phys. Chem., 1994, 98 (31), P. 7551–7554.
24. Mchale J.M., Auroux A., Perrotta A.J., Navrotsky A. Surface energies and thermodynamic phase stability in nanocrystalline aluminas. Science, 1997, 277 (5327), P. 788–791.
25. Castro R.H.R., Ushakov S.V., et al. Surface energy and thermodynamic stability of gamma-alumina: Effect of dopants and water. Chem. Mater., 2006, 18 (7), P. 1867–1872.
26. Castro R.H.R. On the thermodynamic stability of nanocrystalline ceramics. Mater. Lett., 2013, 96, P. 45–56.
27. Ferrari A.C., Robertson J. Interpretation of Raman spectra of disordered and amorphous carbon. Phys. Rev. B, 2000, 61 (20), P. 14095– 14107.
28. Tuinstra F., Koenig J.L. Raman Spectrum of Graphite. J. Chem. Phys., 1970, 53 (3), P. 1126–1130.
29. Kennedy J.L., Drysdale T.D., Gregory D.H. Rapid, energy-efficient synthesis of the layered carbide, Al4C3. Green Chem., 2015, 17 (1), P. 285–290.
30. Zotov R.A., Molchanov V.V., Volodin A.M., Bedilo A.F. Characterization of the active sites on the surface of Al2O3 ethanol dehydration catalysts by EPR using spin probes. J. Catal., 2011, 278 (1), P. 71–77.
31. Hayashi K., Matsuishi S., Kamiya T., Hirano M. Light-induced conversion of an insulating refractory oxide into a persistent electronic conductor. Nature, 2002, 419 (6906), P. 462–465.
32. Matsuishi S., Toda Y., et al. High-density electron anions in a nanoporous single crystal, [Ca24Al28O64] 4+4e−. Science, 2003, 301 (5633), P. 626–629.
33. Kitano M., Inoue Y., et al. Ammonia synthesis using a stable electride as an electron donor and reversible hydrogen store. Nature Chem., 2012, 4 (11), P. 934–940.
34. Kim S.W., Hosono H. Synthesis and properties of 12CaO 7Al2O3 electride: review of single crystal and thin film growth. Philosophical Magazine, 2012, 92 (19–21), P. 2596–2628.
35. Yakovlev I.V., Volodin A.M., et al. Structure of Carbon-Coated C12A7 Electride via Solid-State NMR and DFT Calculations. J. Phys. Chem. C, 2017, 121 (40), P. 22268–22273.
36. Zaikovskii V.I., Volodin A.M., et al. Effect of carbon coating on spontaneous C12A7 whisker formation. Appl. Surf. Sci., 2018, 444, P. 336–338.
37. Garcia H., Marti V., et al. Generation and conversions of aromatic amine radical cations in acid zeolites. Phys. Chem. Chem. Phys., 2001, 3 (14), P. 2955–2960.
Review
For citations:
Volodin A.M., Bedilo A.F., Stoyanovskii V.O., Zaikovskii V.I. High-temperature synthesis of finely dispersed oxide materials and C12A7:e electrides in carbon nanoreactor conditions. Nanosystems: Physics, Chemistry, Mathematics. 2018;9(4):558-567. https://doi.org/10.17586/2220-8054-2018-9-4-558-567
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