Quantum dot sensitized solar cells have been constructed using photoanodes bearing nanocrystalline titania and CdS, CdSe and ZnS quantum dots. The combined CdSe/CdS system provides enhanced photon absorption in a large range of the visible spectrum, while ZnS plays a passivation and stabilization role. This was verified by micro-Raman scattering studies as a function of light soaking of successively sensitized photoanodes. Annealing of photoanodes resulted in increasing quantum dot size as verified by both UV-vis diffuse reflectance and Raman spectroscopy. It was also found that a composite CdSxSe1-x species was formed at the interface of CdS and CdSe layer, which constitutes a stabilization factor and is further stabilized by annealing, that influences the electric characteristics of the sensitized photoanodes. Single CdS sensitizers, when annealed gave increased photocurrents but suffered a fast decay. Annealing of fully sensitized photoanodes gave a diverse behavior, markedly stabilizing photocurrents under N-2 atmosphere. All cells worked well by using a Pt-free cathode made by chemically growing Cu2S on a brass foil. The employed innovative cell structure provided liberty in designing and optimizing the device geometry. (C) 2013 Elsevier B.V. All rights reserved.