Narrow-band-gap semiconductor quantum dots (QDs) have been the subject of considerable interest as the promising candidates for replacing the sensitizers in dye-sensitized solar cells (DSSCs). The use of semiconductor QDs as the sensitizers has some advantages over the use of dye molecules in sensitized solar cell applications. In this study, we characterize the photovoltaic properties of CdSe QD-sensitized solar cells (QDSSCs) made from TiO₂ nanoparticles electrodes. In addition, ZnS was coated on the CdSe QDs and the effect of ZnS coating on the photovoltaic properties were investigated. CdSe QDs were adsorbed onto nanostructured TiO₂ electrodes for different times using a chemical bath deposition (CBD) method for QDSSCs applications. The optical absorption and current-voltage characteristics of these devices were investigated. The optical absorption was characterized using a photoacoustic (PA) technique which is a powereful tool for characterizing the optical absorption of opaque and scattered samples, because the PA signal is directly proportional to the thermal energy resulting by nonradiative processes. The size of CdSe QDs increases with the increase of adsorption time and there is an optimum CdSe adsorption time for achieving the best photovoltaic conversion efficiency. The photovoltaic properties of short circuit current intensity, open voltage, and photovoltaic conversion efficiency are significantly improved by surface modification with ZnS. An efficiency as high as 2.02% for the CdSe QDSSC is achived under the solar illumication of 100 mW/cn².