Conjugated organic dyes for dye-sensitized solar cells

629-634A new metal-free sensitizer 2-[3-(4-dimethyl amino-phenyl)-allylidene]-malonic acid (2) has been synthesized by the condensation of N,N'-dimethylaminocinnaldehyde and malonic acid. This dye has two carboxyl groups on the same carbon atom, which act as better electron withdrawing groups in addition to providing effective anchoring to titanium dioxide. The new dye has characterized by UV –Vis, 1H NMR and CHN analysis. Dye-sensitized nanocrystalline-titanium dioxidese miconductor solar cells (DSSC) have been tested in a stable and durable redox electrolyte. The efficiency of dye is as high as 1.38%. The dye molecule is thermally stable up to 100oC