Characterization of some metal-free organic dyes as photosensitizer for nanocrystalline ZnO-based dye sensitized solar cells

We report the photoelectrochemical characteristics of some biologically used dye: Bromophenol, Ponceau S, Sudan IV, Giemsa, and Acridine Orange as sensitizers. The JSC from 2.5 to 0.47 mA cm−2 with the order Bromophenol > Ponceau S > Sudan IV > Giemsa > Acridine orange, the VOC from 642 to 384 mV, the fill factor (FF) from 0.61 to 0.40, and Pmax from 855 to 84 μW cm−2 were obtained from the DSSCs sensitized with these metal free organic dyes. Among these dyes, Bromophenol gave the best performance as sensitizer with maximum current, which is due to the better interaction between the hydroxyl groups of the dye on the surface of ZnO porous film. Incident photon- to-current conversion efficiency (IPCE) achieved with the use of these dyes follows the order Ponceau S > Sudan IV > Bromophenol > Giemsa > Acridine orange.

► Sensitizers studied: Bromophenol, Ponceau S, Sudan IV, Giemsa, and Acridine orange. ► These dyes were used to sensitize ZnO thin film electrodes in DSSCs. ► Among the dyes studied, bromophenol showed the best performance as sensitizer. ► Using bromophenol as sensitizer, JSC = 2.57 mA cm−2 and VOC = 642 mV were achieved.