Organic Dyes with Hydrazone Moieties: A Study of Correlation between Structure and Performance in the Solid-State Dye-Sensitized Solar Cells

New metal-free organic dyes for solid-state dye-sensitized solar cells, employing a hydrazone fragment, have been synthesized and investigated. These sensitizers are obtained from relatively cheap starting materials, without the use of expensive catalysts, rigorously anhydrous or oxygen-free conditions. Correlation between the structure of hydrazone-containing dyes and the performance of the solid-state DSSC is investigated. The highest obtained solid-state device conversion efficiency, under standard AM 1.5G illumination (100 mW cm^–2), was 4.5% (<i>J</i>_SC = 8.03 mA cm^–2, <i>V</i>_OC = 880 mV, <i>FF</i> = 0.64)