Anodic and cathodic dye-sensitized solar cells (DSC's): different materials, different performances and different perspectives

In DSCs one of the main factors that control the effective conversion of solar radiation into electrical energy is related with the mesoporous features of the semiconductor surface [1]. This is because a mesoporous surface allows the anchoring of a sufficiently large number of dye-sensitizing molecules per unit area and brings about an overall increase of photocurrent density in the DSC with respect to a compact layer of sensitized semiconductor. The surface of a photoactive electrode in a DSC thus represents an example of smart surface the functionality of which mainly derives from the feature of porosity. The present contribution reports on the preparation and characterization of photoactive electrodes with engineered surfaces for DSCs. Electrode materials include both n- and p-types of semiconducting metal oxides sensitized with appropriate dyes for the definition of anodic, cathodic and tandem DSCs [2]. The photoelectrochemical characterization of sealed cells based on the different photoelectrodes, and the analysis of the effects of accelerated aging through cycles of optical and thermal stress will be presented and compared. A short analysis of the perspectives of utilization for the different types of DSCs will be finally given.