  Solar cells with the structure ITO-PEDOT:PSS-Ag:SnS-Al were fabricated with
the active layer of tin sulphide with silver nano-particles (Ag:SnS) grown by
thermal co-evaporation. To understand the influence of the silver nanoparticles
on the energy conversion process, various cells with varying active layer
thicknesses were compared. Results showed that the Ag nanoparticles act as
scattering centers, resulting in longer optical path lengths for incident
light. This in turn results in more charge carriers being generated and thus
enhances the efficiency of the structure as compared to the pristine
ITO-PEDOT:PSS-SnS-Al structure. The plasmonic solar cells of SnS showed an
improvement of more than 40\%. The results are encouraging and suggests more
concerted effort needs to be made on SnS.
