New 3-aryl-2-cyano-acrylohydrazide compounds as effective sensitizers for dye-sensitized solar cells: Photovoltaic performance over the standard dye N719 upon co-sensitization

Abstract

Four novel 3-aryl-2-cyano-N'-(4-(diphenylamino)benzylidene)acrylohydrazide dyes 5–8 were developed, synthesized, and evaluated as sensitizers for dye-sensitized solar cells (DSSCs). The novel dyes are based on triphenylamine as a strong donor moiety conjugated with different acceptor/anchoring moieties. From their DSSC performance, the power conversion efficiency values (PCE) of the compounds were as follows: compound 5 (2.49%); compound 6 (3.46%); compound 7 (3.68%); compound 8 (5.60%); and standard compound N719 (6.95%). As indicated by the results, compound 8 shows the highest results compared to the other compounds. As a result, compound 8 gave a reasonable result when applied in DSSCs and its efficiency is close to the standard dye. It was used as a co-sensitizer along with N719 to improve the properties of the N719 dye. Using compound 8 in conjunction with the standard dye improved the photovoltaic performance of N719. Interestingly, devices that rely on the compound 8 + N719 co-sensitization approach had greater photocurrent and photovoltage than the standard N719 dye, generating a power conversion efficiency (PCE) of 9.80%. This improved performance was mostly due to the improved JSC and VOC values.