An inexpensive and efficient pyridine-based additive for the electrolyte of dye-sensitized solar cells

We report on the synthesis and application of an inexpensive pyridine-based additive allyl isonicotinate (AIN) for the efficient dye-sensitized solar cells (DSCs). AIN can be quickly synthesized at room temperature without any solvent. The presence of AIN in the electrolyte enhances the open-circuit voltage (Voc), fill factor (FF) and short-circuit photocurrent (Jsc), consequently improving the energy conversion efficiency (η) from 6.5% to 8.2%. The impedance experiments show that the adsorption of AIN leads to the negative shift of the conduction band edge of the dye-sensitized TiO2 around 55 mV. The presence of AIN in the electrolyte can obviously suppress the recombination of the injected electrons, increasing the lifetime of electrons in the TiO2. The negative shift of the conduction band edge and the suppression of the recombination of the injected electrons contribute to the higher power conversion efficiency.