A low-temperature route for the synthesis of nanocrystalline LaB{sub 6}

Journal Article · Fri Feb 15 00:00:00 EST 2008 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2007.12.011· OSTI ID:21043890

Maofeng, Zhang ^[1]; Liang, Yuan ^[2]; Xiaoqing, Wang; Hai, Fan; Xuyang, Wang; Xueying, Wu; Haizhen, Wang ^[1]

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1. Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemistry, University of Science and Technology of China, Hefei 230026 (China)
2. Agricultural Department, Shangqiu Vocational and Technical College, Shangqiu 476100 (China)

Nanocrystalline lanthanum hexaboride (LaB{sub 6}) with mean particle size of 30 nm has been successfully synthesized at 400 deg. C in an autoclave starting from metallic magnesium powder, NaBH{sub 4} and LaCl{sub 3}. In this case, by using B{sub 2}O{sub 3} instead of NaBH{sub 4}, LaB{sub 6} nanocubes with mean size of {approx}200 nm were formed at 500 deg. C. The X-ray diffraction (XRD) pattern can be indexed as cubic LaB{sub 6} with the lattice constant of a=4.151 A for LaB{sub 6} nanoparticles and 4.154 A for LaB{sub 6} nanocubes. An atomic ratio of La and B as 1:5.94 was determined from EDS for LaB{sub 6} nanoparticles. XPS data of LaB{sub 6} nanocubes indicate the atomic ratio of La to B as 1:5.95. Raman spectra indicate the formation of LaB{sub 6}. - Graphical abstract: Nanocrystalline lanthanum hexaboride (LaB{sub 6}) with mean particle size of 30 nm has been successfully synthesized at 400 deg. C in an autoclave starting from NaBH{sub 4}, LaCl{sub 3} and metallic magnesium powder. In this case, by using B{sub 2}O{sub 3} instead of NaBH{sub 4}, LaB{sub 6} nanocubes with mean size of {approx}200 nm were formed at 500 deg. C. In comparison with previous routes, the present route allows for the formation of nanocrystalline LaB{sub 6} through a simpler process and at a much lower synthesis temperature.

• OSTI ID: 21043890
• Journal Information: Journal of Solid State Chemistry, Vol. 181, Issue 2; Other Information: DOI: 10.1016/j.jssc.2007.12.011; PII: S0022-4596(07)00528-2; Copyright (c) 2008 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
BORON OXIDES
CRYSTALS
LANTHANUM BORIDES
LANTHANUM CHLORIDES
LATTICE PARAMETERS
MAGNESIUM
NANOSTRUCTURES
PARTICLE SIZE
RAMAN SPECTRA
SYNTHESIS
TEMPERATURE RANGE 0400-1000 K
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY