Synthesis of lanthanum oxyfluoride by grinding lanthanum oxide with poly (tetrafluoroethylene)

  • Lee Jaeryeong (Korea Institute of Geoscience and Mineral Resources) ;
  • Ahn Jonggwan (Korea Institute of Geoscience and Mineral Resources) ;
  • Kim Dongjin (Korea Institute of Geoscience and Mineral Resources) ;
  • Shin Heeyoung (Korea Institute of Geoscience and Mineral Resources) ;
  • Chung Hunsaeng (Korea Institute of Geoscience and Mineral Resources) ;
  • Saito Fumio (Tohoku University)
  • Published : 2003.11.01

Abstract

Lanthanum oxyfluoride can be synthesized by mechanochemical (MC) reaction between lanthanum oxide ($La_2O_3$) and polytetrafluoroethylene (PTFE, ($({CF_2CF_2}_n)$) in air using a planetary mill. MC reaction between the two materials induced from intensive grinding operation. The MC reaction is almost finished by 240min, and the products ground for 240min or more are composed of LaOF, amorphous $La(CO_3)F$ and amorphous carbon (C). Heating this MC reaction products at $600^{\circ}C$ enables us to eliminate amorphous C and decompose $La(CO_3)F$ into LaOF, so that pure LaOF material can be obtained as the final product. The average particle size of the final product (purified LaOF) is around few ten nanometers.

Keywords