journal article·2018-03

Effects of milling parameters on the microstructural and thermal properties of nanocrystalline lanthanum hexaboride powders

Duygu Ağaoğulları, Özge Balcı, M. Lütfi Öveçoğlu, İsmail Duman

Publisher page

Abstract

This study reports the effects of some milling parameters (duration, ball-to-powder weight ratio (BPR), process control agent (PCA)) on the fabrication of nanocrystalline LaB6 powders via a combined process of mechanochemical synthesis (MCS) and acid leaching, starting from La2O3-B2O3-Mg powder blends. MCS was carried out in a high-energy ball mill (SPEX™ 8000D Mixer/Mill, at 1200 rpm) using hardened steel vial and balls under Ar atmosphere. As-synthesized products were leached out with 4 M HCl from unwanted MgO phase and probable Fe impurities. When a BPR of 18:1 was used, 5 h of MCS and leaching yielded LaB6 powders with an average particle size of 100 nm, containing a very small amount of FeB49 phase. Pure LaB6 powders were obtained with an average particle size of 53 nm after 12 h of MCS of the 0.5 wt% PCA added La2O3-B2O3-Mg powder blends with a BPR of 10:1 and after leaching.
Source: openaire · Quality: candidate unverified · Source record ↗

Research context

OpenAlex topics: Rare-earth and actinide compounds · Advanced materials and composites · Boron and Carbon Nanomaterials Research

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (38)

Show source-provided references
1. Zhang, M., Yuan, L., Wang, X., Fan, H., Wang, X., Wu, X., Wang, H., Qian, Y.: A low-temperature route for the synthesis of nanocrystalline LaB6. J Solid State Chem. 181, 294–297 (2008)10.1016/j.jssc.2007.12.011 ↗
2. Xu, J., Zhao, Y., Zou, C.: Self-catalyst growth of LaB6 nanowires and nanotubes. Chem Phys Lett. 423, 138–142 (2006)10.1016/j.cplett.2006.03.049 ↗
3. Gao, R., Min, G., Yu, H., Zheng, S., Lu, Q., Han, J., Wang, W.: Fabrication and oxidation behavior of LaB6-ZrB2 composites. Ceram Int. 31, 15–19 (2005)10.1016/j.ceramint.2004.02.006 ↗
4. Baranovskiy, A.E., Grechnev, G.E., Fil, V.D., Ignatova, T.V., Logosha, A.V., Panfilov, A.S., Svechkarev, I.V., Shitsevalova, N.Y., Filippov, V.B., Eriksson, O.: Electronic structure, bulk and magnetic properties of MB6 and MB12 borides. J. Alloy. Compd. 442, 228–230 (2007)10.1016/j.jallcom.2006.07.142 ↗
5. Wang, X., Jiang, Y., Lin, Z., Qi, K., Wang, B.: Field emission characteristics of single crystal LaB6 field emitters fabricated by electrochemical etching method. J Phys D Appl Phys. 42, 1–4 (2009)
6. Swanson, L.W., McNeely, D.R.: Work functions of the (001) face of the hexaborides of Ba, La, Ce and Sm. Surf Sci. 83, 11–28 (1979)10.1016/0039-6028(79)90477-1 ↗
7. Loboda, P.I., Kysla, H.P., Dub, S.M., Karasevska, O.P.: Mechanical properties of the monocrystals of lanthanum hexaboride. Mater Sci. 45, 108–113 (2009)10.1007/s11003-009-9167-6 ↗
8. Chen, C.H., Aizawa, T., Iyi, N., Sato, A., Otani, S.: Structural refinement and thermal expansion of hexaborides. J. Alloy. Compd. 366, L6–L8 (2004)10.1016/S0925-8388(03)00735-7 ↗
9. Perkins, C.L., Trenary, M., Tanaka, T., Otani, S.: X-ray photoelectron spectroscopy investigation of the initial oxygen adsorption sites on the LaB6 (100) surface. Surf Sci. 423, L222–L228 (1999)10.1016/S0039-6028(98)00936-4 ↗
10. Selvan, R.K., Genish, I., Perelshtein, I., Moreno, J.M.C., Gedanken, A.: Single step, low-temperature synthesis of submicron-sized rare earth hexaborides. J Phys Chem C. 112, 1795–1802 (2008)10.1021/jp0765502 ↗
11. Wen, C.H., Wu, T.M., Wei, W.C.: Oxidation kinetics of LaB6 in oxygen rich conditions. J Eur Ceram Soc. 24, 3235–3243 (2004)10.1016/j.jeurceramsoc.2003.11.016 ↗
12. Balakrishnan, G., Lees, M.R., Paul, D.M.K.: Rare earth hexaborides: large single crystals. J Magn Magn Mater. 272-276, 601–602 (2004)10.1016/j.jmmm.2003.12.1390 ↗
13. Ahmed, H., Kanitkar, P.L., Dharmadhikari, C.V., Joag, D.S.: A new method for melting and recrystallization of lanthanum hexaboride (LaB6) for preparing field emitters. J Phys E Sci Instrum. 9, 4–5 (1976)10.1088/0022-3735/9/1/002 ↗
14. Zhang, H., Tang, B., Zhu, P.W., Zhang, Q., Zhou, O., Qin, L.C.: Fabrication of lanthanum hexaboride single nanowire field emitter and their field emission properties. T Mrs Jap. 32, 747–750 (2007)
15. Zhang, H., Tang, J., Zhang, Q., Zhao, G., Yang, G., Zhang, J., Zhou, O., Qin, L.C.: Field emission of electrons from single LaB6 nanowires. Adv Mater. 18, 87–91 (2006)10.1002/adma.200500508 ↗
16. Mitterer, C., Waldhauser, W., Beck, U., Reiners, G.: Structure and properties of decorative rare-earth hexaboride coatings. Surf Coat Tech. 86-87, 715–721 (1996)10.1016/S0257-8972(96)02971-4 ↗
17. Li, P., Tian, W., Wang, D., Liu, X.: Grain refining potency of LaB6 on aluminum alloy. J Rare Earth. 30, 1172–1176 (2012)10.1016/S1002-0721(12)60200-2 ↗
18. Ji, X.H., Zhang, Q.Y., Xu, J.Q., Zhao, Y.M.: Rare-earth hexaborides nanostructures: recent advances in materials, characterization and investigations of physical properties. Prog Solid State Ch. 39, 51–69 (2011)10.1016/j.progsolidstchem.2011.04.001 ↗
19. Motojima, S., Takahashi, Y., Sugiyama, K.: Chemical vapor growth of LaB6 whiskers and crystals having a sharp tip. J Cryst Growth. 44, 106–109 (1978)10.1016/0022-0248(78)90333-0 ↗
20. Brewer, J.R., Deo, N., Wang, Y.M., Cheung, C.L.: Lanthanum hexaboride nanoobelisks. Chem Mater. 19, 6379–6381 (2007)10.1021/cm702315x ↗
21. Dou, Z., Zhang, T., Zhang, Z., Zhang, H., He, J.: Preparation and characterization of LaB6 ultra fine powder by combustion synthesis. T Nonferr Metal Soc. 21, 1790–1794 (2011)10.1016/S1003-6326(11)60932-1 ↗
22. Post, B., Moskowitz, D., Glaser, F.W.: Borides of rare earth metals. J Am Chem Soc. 78, 1800–1802 (1956)10.1021/ja01590a007 ↗
23. Otani, S., Honma, S., Yajima, Y., Ishizawa, Y.: Preparation of LaB6 single crystals from a boron-rich molten zone by the floating zone method. J Cryst Growth. 126, 466–470 (1993)10.1016/0022-0248(93)90052-X ↗
24. Wang, L., Xu, L., Ju, Z., Qian, Y.: A versatile route for the convenient synthesis of rare-earth and alkaline-earth hexaborides at mild temperatures. CrystEngComm. 12, 3923–3928 (2010)10.1039/c001167c ↗
25. Hasan, M., Sugo, H., Kisi, E.: Low temperature carbothermal and boron carbide reduction synthesis of LaB6. J Alloy Compd. 578, 176–182 (2013)10.1016/j.jallcom.2013.05.008 ↗
26. Jha, M., Patra, R., Ghosh, S., Ganguli, A.K.: Novel borothermal route for the synthesis of lanthanum cerium hexaborides and their field emission properties. J Solid State Chem. 194, 173–178 (2012)10.1016/j.jssc.2012.04.051 ↗
27. Yuan, Y., Zhang, L., Liang, L., He, K., Liu, R., Min, G.: A solid-state reaction route to prepare LaB6 nanocrystals in vacuum. Ceram Int. 37, 2891–2896 (2011)10.1016/j.ceramint.2011.03.073 ↗
28. Ağaoğulları, D., Duman, İ., Öveçoğlu, M.L.: Synthesis of LaB6 powders from La2O3, B2O3 and Mg blends via a mechanochemical route. Ceram Int. 38, 6203–6214 (2012)10.1016/j.ceramint.2012.04.073 ↗
29. Ağaoğulları, D., Balcı, Ö., Öveçoğlu, M.L., Duman, İ.: Preparation of LaB6 powders via calciothermic reduction using mechanochemistry and acid leaching. KONA Powder Part J. 33, 203–218 (2016)10.14356/kona.2016001 ↗
30. Suryanarayana, C.: Mechanical alloying and milling. Prog Mater Sci. 46, 1–184 (2001)10.1016/S0079-6425(99)00010-9 ↗
31. El-Eskandarany, M.S.: Mechanical Alloying for Fabrication of Advanced Engineering Materials. Noyes Publications, Norwich (2001)
32. Murty, B., Ranganathan, R.: Novel materials synthesis by mechanical alloying/milling. Int Mater Rev. 43, 101–141 (1998)10.1179/imr.1998.43.3.101 ↗
33. Gutman, E.M.: Mechanochemistry of materials. Cambridge International Publishing, Cambridge (1998)
34. Levitas, V.I.: Continuum mechanical fundamentals of mechanochemistry. In: Domnich, V., Gogotsi, Y. (eds.) High pressure surface science and engineering, pp. 161–292. IOP Publishing Ltd., Bristol (2004)
35. Ağaoğulları, D., Balcı, Ö., Duman, İ., Öveçoğlu, M.L.: Microstructure and properties of nanocrystalline LaB6 powders synthesized in a high-energy planetary ball mill. Proceedings of the 22nd International Conference on Metallurgy and Materials, METAL 2013, E-46. ISBN 978-80-87294-39-0, Czech Republic (2013)
36. Ağaoğulları, D., Balcı, Ö., Gökçe, H., Duman, İ., Öveçoğlu, M.L.: Synthesis of magnesium borates by mechanically activated annealing. Metall Mater Trans A. 43A, 2520–2533 (2012)10.1007/s11661-012-1109-5 ↗
37. Ağaoğulları, D., Balcı, Ö., Öveçoğlu, M.L., Suryanarayana, C., Duman, İ.: Synthesis of bulk nanocrystalline samarium hexaboride. J Eur Ceram Soc. 35, 4121–4136 (2015)10.1016/j.jeurceramsoc.2015.07.037 ↗
38. McKelvy, M.J., Eyring, L., Storms, E.K.: Analytical and structural analysis of the lanthanum-deficient lanthanum hexaboride. J Phys Chem. 88, 1785–1790 (1984)10.1021/j150653a024 ↗