Characterization of CdS and ZnS Nanoparticle Semiconductors: for Optoelectronics Application
Abstract: In this work, CdS
and ZnS semiconducting colloid nanoparticles coated with organic shell,
containing either SO−3 or NH+2 groups, were deposited as thin films using the
technique of electrostatic self-assembly. The films produced were characterized
with UV-vis spectroscopy - for optical properties; mercury probe - for
electrical characterisation; and photon counter - for electroluminescence
study. UV-vis spectra show a substantial blue shift of the main absorption band
of both CdS and ZnS, either in the form of solutions or films, with respect to the
bulk materials. The calculation of nanoparticles’ radii yields the value of
about 1.8 nm for both CdS and ZnS.Current-voltage (I-V) and
capacitance-frequency (C-f) measurements of polyelectrolyte/nanoparticles (CdS
or ZnS) films suggest the tunnelling behaviour in the films while capacitance-
voltage (C-V) and conductance-voltage (G-V) measurements suggest that these
nanoparticles are conductive. The electroluminescence was detected in sandwich
structures of (PAH/CdS/PAH)N using a photon counting detector, but not in the
case of ZnS films.
Author: Suryajaya
Journal Code: jpfisikagg110005
