In this paper, CuInS2 (CIS) nanoparticles were synthesized successfully via a new copper precursor
[bis(acetylacetonato)copper(II)], [Cu(acac)2]; at room temperature by ultrasonic method. The effect of sulfur source,
solvent, and reaction time was investigated on product morphology and particle size. A series of analyses was performed
to characterize the CuInS2 microsphere including X-ray diffraction (XRD), scanning electron microscopy (SEM),
transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. CuInS2 nanoparticles were prepared
and coated on FTO. Later, the coated FTO was sintered so that a compact and dense CuInS2 film was produced and
measured for photovoltaic characteristics such as Voc, Jsc and FF.