ferrite nanoparticles for ferrofluids; properties of magnets objectives: --synthesize ferrimagnetic...
Post on 21-Dec-2015
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Ferrite Nanoparticles for Ferrofluids;Properties of Magnets
Objectives:
--Synthesize ferrimagnetic nanoparticle fluid
--Observe differences in magnetic behavior between bulk magnets and nanoparticles
Examples of Nanotechnology
ZnO nanowire UV lasers: 100 nm diameter
100 nm Silicon Features
100 nm Silicon Features
Ferrite (Magnetite), Fe3O4
--Spinel structure: Fe coordinated by 4 or 6oxygen atoms
--Compass needle of ancient world: “lodestone”
--Ferrimagnetic
Types of Magnetism In Inorganic Compounds
Biomineralization of Ferrite Nanoparticles
Biomineralization of Ferrite Nanoparticles
Ferrite Nanoparticle Synthesis
--Mixture of Fe+3 and Fe+2 in H2O: provides O for oxide formation
--HCl: solvates iron chlorides, prevent rapid precipitation of oxide
--Hydrolysis/condensation reactions, catalyzed by water
--NH3 scavenges Cl- ligands: NH4+Cl-
Behavior of nanoparticle magnetic domains within fluid vs. bulk magnetic solids
Experimental
--Add sufficient FeCl2
--REMOVE ALL LIQUID from reaction mixture
--DO NOT ADD too much surfactant. <1 ml to start.