Rapid mixing: A route to synthesize magnetite nanoparticles with high moment
Abstract
We demonstrate the impact of rapid mixing of the precursors in a time scale of milliseconds on the reaction rate and magnetic properties of co-precipitated magnetite with a custom-made mixer. The mixed volume is directed into a desk-top AC susceptometer to monitor the magnetic response from the growing particles in real-time. These measurements indicate that the reaction is mostly completed within a minute. The obtained superparamagnetic nanoparticles exhibit a narrow size distribution and large magnetization (87 Am2 kg-1). Transmission electron micrographs suggest that rapid mixing is the key for better crystallinity and a more uniform morphology leading to the observed magnetization values.
- Publication:
-
Applied Physics Letters
- Pub Date:
- November 2011
- DOI:
- 10.1063/1.3662965
- Bibcode:
- 2011ApPhL..99v2501F
- Keywords:
-
- iron compounds;
- magnetic moments;
- magnetic particles;
- magnetisation;
- mixing;
- nanofabrication;
- nanomagnetics;
- nanoparticles;
- paramagnetic materials;
- precipitation (physical chemistry);
- transmission electron microscopy;
- 81.16.-c;
- 75.50.Tt;
- 75.75.Cd;
- 75.60.Ej;
- 75.20.Ck;
- 75.30.Cr;
- Methods of nanofabrication and processing;
- Fine-particle systems;
- nanocrystalline materials;
- Magnetization curves hysteresis Barkhausen and related effects;
- Nonmetals;
- Saturation moments and magnetic susceptibilities