minerals such as iron, potassium and calcium [19,31]. A
change from colourless to deeply brick-red colour indi-
cated the formation of nanoparticles. The formation of
Se-nanoballs was examined at different interval of time.
It took nearly 6 min to start conversion of Se ion to Se
nanoparticles which was indicated by a decrease in Se
ion concentration in the solution. The nature of nano-
particles was analysed by TEM images. It showed that
the diameter of nanoballs ranges between 3 and 18 nm.
They were found to be encapsulated with a thin poly-
morphic layer. The formation of Se nanoparticles was
confirmed from the energy dispersive x-ray spectros-
copy. The Se nanoballs were identified from their char-
acteristic absorption peaks at 1.37KeV, 11.22KeV and
12.49KeV [32]. The morphology of Se nanoparticles can
be analysed by x-ray diffraction (XRD) analysis. The
broad diffraction peak suggests the presence of amorph-
ous nature of Se nanoparticles [33]. Their particle size
[34] has been found to be of the order of 12 nm.