Catalytic effect of potassium carbonate on carbothermic production of hexagonal boron nitride

ÇAMURLU H. E., GENÇER A., BECER B., ÖZDOĞAN S.

CERAMICS INTERNATIONAL, vol.39, no.8, pp.8589-8595, 2013 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 39 Issue: 8
  • Publication Date: 2013
  • Doi Number: 10.1016/j.ceramint.2013.04.032
  • Journal Name: CERAMICS INTERNATIONAL
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.8589-8595
  • Keywords: Powders: chemical preparation, Hexagonal boron nitride, VAPORIZATION
  • Akdeniz University Affiliated: Yes

Abstract

Effect of potassium carbonate addition on the carbothermic formation of hexagonal boron nitride (hBN) was investigated by keeping the K2CO3 added B2O3+C mixtures in nitrogen atmosphere at 1400 degrees C for 40-160 min. K2CO3 amount was varied in the range of 10-60 wt% of the B2O3+C mixture. Products were subjected to XRD and quantitative analyses, SEM and TEM observations, and particle size measurement. Amount of hBN increased considerably with K2CO3 addition; also particle size and crystallinity improved. Catalytic role of K2CO3 was suggested as forming a potassium borate melt in which hBN particles form, in addition to carbothermic formation reaction. Effect of K2CO3 on increasing the hBN amount decreased when it was used over 40%. This was attributed to the rapid evaporation of the formed potassium borate liquid. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Effect of potassium carbonate addition on the carbothermic formation of hexagonal boron nitride (hBN) was investigated by keeping the K2CO3 added B2O3+C mixtures in nitrogen atmosphere at 1400 degrees C for 40-160 min. K2CO3 amount was varied in the range of 10-60 wt% of the B2O3+C mixture. Products were subjected to XRD and quantitative analyses, SEM and TEM observations, and particle size measurement. Amount of hBN increased considerably with K2CO3 addition; also particle size and crystallinity improved. Catalytic role of K2CO3 was suggested as forming a potassium borate melt in which hBN particles form, in addition to carbothermic formation reaction. Effect of K2CO3 on increasing the hBN amount decreased when it was used over 40%. This was attributed to the rapid evaporation of the formed potassium borate liquid. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.