Characterization of Iron Oxide Nanoparticles Synthesized by Flame Synthesis

화염법으로 제조된 산화철 나노입자의 특성평가

  • 양상선 (서울대학교 기계항공공학부 나노입자제어기술연구단) ;
  • 이고르알트만 (서울대학교 나노입자제어기술연구단 호주 그리피스대학교 환경공학과) ;
  • 피터피키차 (서울대학교 나노입자제어기술연구단) ;
  • 최만수 (서울대학교 기계항공공학부 나노입자제어기술연구단)
  • Published : 2004.11.03

Abstract

Size and crystalline phase changes of $Fe_{2}O_{3}$ nanoparticles formed in a $H_{2}/O_{2}$ flame have been investigated. At flame temperatures below $1350^{\circ}C$, the mean particle size increased monotonously with the distance from the burner edge; but in high-temperature flames above $1650^{\circ}C$, it suddenly decreased from 20 nm to ${\sim}3$ nm with the distance from the burner edge. The results of X-ray diffraction and HRTEM showed that this sudden reduction of the size of nanoparticles was accompanied by a partial phase transformation from ${\gamma}$-$Fe_{2}O_{3}$ into ${\alpha}$-$Fe_{2}O_{3}$. We suggest the structural instability due to ${\gamma}-$ to ${\alpha}-phase$ transformation as a mechanism for a rapid fragmentation of 20 nm particles into 3 nm ones.

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