Abstract
NiFe2O4 powders with large-sized, hollow, and thin wall structures were directly prepared by spray pyrolysis from a spray solution containing citric acid. These as-prepared powders converted into nanosized NiFe2O4 powders after post-treatment at high temperatures between 600 and 1000°C. Phase-pure NiFe2O4 powders were obtained at post-treatment temperatures between 700 and 1000°C. When the post-treatment temperatures were increased from 700 to 1000°C, the BET surface areas of the NiFe2O4 powders decreased from 23.4 to 11.8 m2/g and their mean sizes increased from 47.8 to 94.7 nm, respectively. The saturation magnetizations of the powders changed from 32 to 44 emu/g according to changes in the post-treatment temperatures. The coercivities of the powders post-treated at temperatures of 700 and 800°C were 118 and 130 Oe, respectively.
Original language | English |
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Pages (from-to) | 1069-1073 |
Number of pages | 5 |
Journal | Journal of the Ceramic Society of Japan |
Volume | 117 |
Issue number | 1370 |
DOIs | |
Publication status | Published - 2009 Oct |
Externally published | Yes |
Keywords
- Nano powder
- Nickel ferrite
- Spray pyrolysis
ASJC Scopus subject areas
- Ceramics and Composites
- Chemistry(all)
- Condensed Matter Physics
- Materials Chemistry