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)

Branched methoxydiphenylamine-substituted fluorene derivatives as hole transporting materials for high-performance perovskite solar cells

Small-molecule hole transporting materials based on methoxydiphenylamine-substituted fluorene fragments were synthesized and incorporated into a perovskite solar cell, which displayed a power conversion efficiency of up to 19.96%, one of the highest conversion efficiencies reported. The investigated hole transporting materials were synthesized in two steps from commercially available and relatively inexpensive starting reagents, resulting in up to fivefold cost reduction of the final product compared with spiro-OMeTAD. Electro-optical and thermoanalytical measurements such as UV/Vis, thin-film conductivity, hole mobility, DSC, TGA, ionization potential and current voltage scans of the full perovskite solar cells have been carried out to characterize the new materials