M. Behboudnia et P. Sen, Systematics in the nanoparticle band gap of ZnS and Zn1-xMxS (M = Mn, Fe, Ni) for various dopant concentrations - art. no. 035316, PHYS REV B, 6303(3), 2001, pp. 5316
We report a detailed study of the formation of semiconductor nanoparticles
of the important compound ZnS and its Mn-doped variant Zn(1-x)MnxS inside r
everse micelle microreactors, by carefully varying the size of the reverse
micelles at a fixed Mn concentration with x=0.01. Dynamic light scattering
techniques allow us to characterize the microreactor sizes and correlate th
em with the size of the resultant nanoparticles. Band gap measurements empl
oying UV-visible spectroscopy clearly show that Mn-doped samples have highe
r band gaps, largely independent of the size of the vessel they were create
d in. This observation reflects the role of Mn as an inhibitor to the growt
h of the nanoparticles. This is further strengthened by the observation of
inhibition by other elements of the first row transition metals. Substituti
on with Fe and Ni shows similar trends in band gap (and hence particle size
) variation with the reaction chamber size as well as with the dopant conce
ntration x of these elements, while such variations on substitution with Mn
are distinct, possibly because the sulfides of Zn and Mn are isostructural
.