(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 & Processing Technology, Beijing 100076, China)
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DOI:
10.7502/j.issn.1674-3962.2012.07.08
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Abstract:
Carbothermal reduction acted synergistically with solgel method to synthesize zirconium diboride (ZrB2) Nanoparticles was conducted using zirconium npropoxide (Zr(OPr)4), boric acid (H3BO3), sucrose (C12H22O11), and acetic acid (AcOH).Here, C12H22O11 was selected since it can be completely decomposed to carbon.Thus, carbon might be accounted precisely for the carbothermal reduction reaction.We investigated the influence of the gelation temperature on the morphology of ZrB2 particles.Increasing the gelation temperature, the particle shapes changed from spherelike particles at 65 ℃ to particles chains at 75 ℃, and then rodlike particles at 85 ℃.An indepth HRTEM observation revealed that the nanoparticles of ZrB2 were gradually fused together to evolve into a particle chain, finally into a rodlike shape.These morphologies related to the gelation temperature and obeyed the “oriented attachment mechanism” of crystallography.