Morphology evolution of ZrB{sub 2} nanoparticles synthesized by sol-gel method

Journal Article · Mon Aug 15 00:00:00 EDT 2011 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.05.040· OSTI ID:21580190

Yun, Zhang ^[1]; Yanshan, Jiang; Bin, Zhao; Huiping, Duan ^[1]; Junping, Li; Zhihai, Feng ^[2]

---

1. Key Laboratory of Aerospace Materials and Performance (Ministry of Education), School of Materials Science and Engineering, Beihang University, Beijing 100191 (China)
2. Aerospace Research Institute of Materials and Processing Technology, Beijing 100076 (China)

Zirconium diboride (ZrB{sub 2}) nanoparticles were synthesized by sol-gel method using zirconium n-propoxide (Zr(OPr){sub 4}), boric acid (H{sub 3}BO{sub 3}), sucrose (C{sub 12}H{sub 22}O{sub 11}), and acetic acid (AcOH). Clearly, it was a non-aqueous solution system at the very beginning of the reactions. Here, AcOH was used as both chemical modifier and solvent to control Zr(OPr){sub 4} hydrolysis. Actually, AcOH could dominate the hydrolysis by self-produced water of the chemical propulsion, rather than the help of outer water. C{sub 12}H{sub 22}O{sub 11} was selected, since it can be completely decomposed to carbon. Thus, carbon might be accounted precisely for the carbothermal reduction reaction. Furthermore, we investigated the influence of the gelation temperature on the morphology of ZrB{sub 2} particles. Increasing the gelation temperature, the particle shapes changed from sphere-like particles at 65 deg. C to a particle chain at 75 deg. C, and then form rod-like particles at 85 deg. C. An in-depth HRTEM observation revealed that the nanoparticles of ZrB{sub 2} were gradually fused together to evolve into a particle chain, finally into a rod-like shape. These crystalline nature of ZrB{sub 2} related to the gelation temperature obeyed the 'oriented attachment mechanism' of crystallography. - Graphical Abstract: Increasing the gelation temperature, the particle shapes changed from sphere-like particles at 65 deg. C to a particle chain at 75 deg. C, and then form rod-like particles at 85 deg. C. Highlights: > ZrB{sub 2} nanoparticles were synthesized by sol-gel method in an non-aqueous solution system. > AcOH was used as both chemical modifier and solvent to control Zr(OPr){sub 4} hydrolysis. > C{sub 12}H{sub 22}O{sub 11} was selected since it can be completely decomposed to carbon. > Increasing the gelation temperature, the particles changed from sphere-like to rod-like ones. > Crystalline nature of ZrB{sub 2} obeyed the 'oriented attachment mechanism' of crystallography.

• OSTI ID: 21580190
• Journal Information: Journal of Solid State Chemistry, Vol. 184, Issue 8; Other Information: DOI: 10.1016/j.jssc.2011.05.040; PII: S0022-4596(11)00289-1; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ACETIC ACID
AQUEOUS SOLUTIONS
BORIC ACID
CARBON
CONTROL
CRYSTALLOGRAPHY
GELATION
HYDROLYSIS
MORPHOLOGY
NANOSTRUCTURES
PARTICLES
RODS
SACCHAROSE
SOL-GEL PROCESS
SOLVENTS
SPHERES
SYNTHESIS
TRANSMISSION ELECTRON MICROSCOPY
ZIRCONIUM BORIDES
BORIDES
BORON COMPOUNDS
CARBOHYDRATES
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
DECOMPOSITION
DISACCHARIDES
DISPERSIONS
ELECTRON MICROSCOPY
ELEMENTS
HOMOGENEOUS MIXTURES
HYDROGEN COMPOUNDS
INORGANIC ACIDS
INORGANIC COMPOUNDS
LYSIS
MICROSCOPY
MIXTURES
MONOCARBOXYLIC ACIDS
NONMETALS
OLIGOSACCHARIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
SACCHARIDES
SOLUTIONS
SOLVOLYSIS
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS