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.