Impact of DSSCs structure modification sensitized with phenothiazine derivative on photovoltaic performance

This paper presents the results of a study on the modification of dye-sensitized solar cells (DSSCs) using various phenothiazine derivatives, N719, and a mixture of these. The influence of the solvent used to prepare the dye solution, as well as the use of a TiO2 blocking layer, the addition of a co-adsorbent, or a mixture of dyes with N719 are presented. Characterisation of photoanodes was carried out to determine the UV-Vis absorption properties, morphology, and photovoltaic parameters of the fabricated solar cells. The use of different solvents for the preparation of dye solutions resulted in DSSCs efficiencies in the range of 1.55–7.26%. The most advantageous was using an ACN:t-BuOH mixture, which provided the best efficiency. The application of further modifications in the form of the addition of chenodeoxycholic acid (CDCA), a blocking layer, and the use of a co-sensitization process resulted in an increase in the final efficiency to a value of 8.50%.