Co-sensitization of Structurally Simple Porphyrin and Anthracene-based Dye for Dye-Sensitized Solar Cells.

Since their introduction, dye-sensitized solar cells (DSCs) have achieved a huge success at laboratory level. Recently, research is concentrated to visualize large DSC modules at the commercial platform. In that aspect, we have tested structurally simple porphyrin-based dye SK6 and anthracene-based dye CW10 for DSCs application under simulated 1 sun (AM 1.5G) and indoor light sources. These two dyes can be easily synthesized and yet are efficient with cell performances of ca. 5.42% and ca. 5.75% (without co-adsorbent / additive) for SK6 and CW10, respectively, under AM 1.5G illumination. The power conversion efficiency (PCE) of SK6 reported in this work is the highest than ever reported, this is achieved by optimizing the adsorption of SK6 on TiO photoanode using the most suitable solvent and immersion period. Co-sensitization of SK6 with CW10 on TiO surface has boosted cell performance further and achieved PCE of ca. 6.31% under AM 1.5G illumination. Charge transfer properties of individual and co-sensitized devices at TiO/dye/electrolyte interface were examined via electrochemical impedance spectroscopy. In order to understand the cell performances under ambient light conditions, we soaked individual and co-sensitized devices under T5 and LED light sources in the range of 300 - 6000 lux. The PCE of ca. 22.91% under T5 light (6000 lux) with J = 0.883 mA cm, V = 0.646 V and FF = 0.749 was noted for the co-sensitized device, which equals to a power output of 426 µW cm. These results reveal that DSCs made of structurally simple dyes performed efficiently under both 1 sun (AM 1.5G) and indoor light conditions, which is undoubtedly a significant achievement when it comes to a choice of commercial application.