Mechanochemical synthesis and characterisation of niobium silicide nanoparticles

Didem Ovalı*, Duygu Ağaoğulları, M. Lütfi Öveçoğlu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)

Abstract

Mechanochemical synthesis (MCS) investigations of niobium silicide powders in Nb 2 O 5 –]SiO 2 –]Mg powder mixtures were conducted via high-energy ball milling and leaching by means of process parameters such as the milling duration, initial Nb 2 O 5 crystal structure, and excess Mg amount. The compositional, thermal, and microstructural properties of the products were characterised using X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), particle size analysis (PSA), stereomicroscopy (SM), scanning electron microscopy (SEM), and transmission electron microscopy/energy-dispersive spectrometry (TEM/EDS). After the 5 h milling of the stoichiometric mixtures, an instantaneous ignition occurred and NbSi 2 , Nb 5 Si 3 , Nb, and MgO phases formed with some residual Mg. In addition, the use of excess Mg inhibited the formation of Nb 5 Si 3 . Afterwards, leaching treatments (in a 4 M HCl solution) completely removed the Mg-based phases from the synthesised products. The XRD calculations revealed that the resultant product consisted of 97 wt% NbSi 2 and 3 wt% Nb 5 Si 3 phases. The TEM analyses indicated that each Nb silicide nanoparticle was coated with a SiO 2 layer. According to random measurements, the average particle size of the Nb silicide cores and average thickness of the SiO 2 layer were approximately 61 and 7.5 nm, respectively.

Original languageEnglish
Pages (from-to)10654-10663
Number of pages10
JournalCeramics International
Volume45
Issue number8
DOIs
Publication statusPublished - 1 Jun 2019

Bibliographical note

Publisher Copyright:
© 2019 Elsevier Ltd and Techna Group S.r.l.

Keywords

  • Electron microscopy
  • Powders: solid state reaction
  • Silicides
  • Transition metal oxides

Fingerprint

Dive into the research topics of 'Mechanochemical synthesis and characterisation of niobium silicide nanoparticles'. Together they form a unique fingerprint.

Cite this