Biomedical Engineering Reference
In-Depth Information
Figure 10.4
SEM images of SiO
2
nanoparticles prepared by the Stöber method.
mL deionized water. h ese magnetic nanoparticles were further used in
the preparation of Fe3O4@Au nanocomposites.
10.4.2 Synthesis of TiO
2
Nanoparticles
Titania particles were produced by a sol-gel method following Sau and
Rogach
[9]. Tetraethyl orthotitanate also known as titanium ethoxide
(TEOT) was used as the Titania precursor. In a typical synthesis proce-
dure ethanol and aqueous solution of metal salts such as NaCl or KBr
was mixed and stirred for 15 min at room temperature in inert atmo-
sphere. h e TEOT was added dropwise and the mixture was continu-
ously stirred for another 30 min. Turbidity appears instantly as soon as
TEOT is added. Stirring was stopped at er 30 min and the mixture was
allowed to age for 150 min. h e dispersion was then i ltered and washed
with ethanol. For fabricating dif erent sizes, dif erent metal salts were
used. Ethanol: NaCl: TEOT (100: 0.4 mL of 0.1 M: 1.7 mL) concentra-
tion produces Titania particles of size 1160 nm and Ethanol: KBr: TEOT
(100: 0.4 mL of 0.1 M: 1.7 mL) concentration produces Titania particles
of size 350 nm.
10.4.3
Synthesis of CdS, PbS and CuS Nanoparticles [10]
With ethanol and thioglycerol (TG) used as organic solvent and surface
capping agent, respectively, CdS, PbS and CuS nanoparticles were prepared
by the reaction between metals and elemental sulphur. All chemicals used
in this experiment were analytical grade and used as received. h e proce-
dure is as follows: dissolve 0.017 g elemental sulphur, 510-4 mol metal salts
and 5×10-3 mol TG in 50 mL ethanol at 70 C. h en, heat the as prepared
solution at 70-80 C for 25 min under stirring. Centrifuge the solution and
