  The unique structural features and suitability of the SiO2 micro particles in
different application areas have mobilized a worldwide interest in the last few
decades. In this report a classical method known as the Stober method has been
used to synthesize silica micro spheres. These microparticles have been
synthesized by the reaction of tetraethyl orthosilicate (Si(OC2H5)4, TEOS)
(silica precursor) with water in an alcoholic medium (e.g. ethanol) in the
presence of KCl electrolyte and ammonia as a catalyst. It has been observed
that the size of the microparticles closely depends on the amount of the TEOS
and ammonia. A decrease in the size of micro particles from 2.1 micrometer to
1.7 micrometer has been confirmed as the amount of TEOS increases from 3.5 ml
to 6.4 ml respectively. In similar way a decrease in the diameter of the micro
particles from 2.1 micrometer to 1.7 micrometer has been observed with increase
in the ammonia content from 3 ml to 9 ml.
