Benzothiazole functionalized diketopyrrolopyrrole photosensitizer for CdS nanowire based DSSC applications

[Display omitted] •We have designed and synthesized benzothiazole functionalized diketopyrrolopyrrole DPP-BTH1 and DPP-BTH2 chromophores.•DPP-BTH1 and DPP-BTH-2 was utilized for fabrication of CdS-NWs based DSSC device.•DSSC devices with DPP-BTH1/CdS and DPP-BTH2/CdS nanowire photoelectrode exhibited η of about 0.30% and 0.45%, respectively.•The PCE of DPP-BTH1/CdS and DPP-BTH2/CdS is three and four-fold higher than that of bare CdS nanowire-based DSSC devices. Although dye sensitized solar cell (DSSC) make promising progress for solar energy conversion to electrical energy, there are still great need for further research work to develop an efficient sensitizer with a simple synthetic protocol. In this study, two chromophores (E)-2-(benzo[d]thiazol-2-yl)-3-(5-(2,5-bis(2-ethylhexyl)-3,6-dioxo-4-(thiophen-2-yl)-2,3,5,6-tetrahydropyrrolo[3,4-c]pyrrol-1-yl)thiophen-2-yl)acrylonitrile (DPP-BTH1) and 3-(5-(2,2-bis(benzo[d]thiazol-2-yl)vinyl)thiophen-2-yl)-2,5-bis(2-ethylhexyl)-6-(thiophen-2-yl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione (DPP-BTH2) are developed with broad range of absorption. The benzothiazole subunit 2-(benzo[d]thiazol-2-yl)acetonitrile (BTH1) and bis(benzo[d]thiazol-2-yl)methane (BTH2) auxiliary subunits were incorporated at the 5-(2,5-bis(2-ethylhexyl)-3,6-dioxo-4-(thiophen-2-yl)-2,3,5,6-tetrahydropyrrolo[3,4-c]pyrrol-1-yl) thiophene-2-carbaldehyde (DPP) core. DSSC devices with DPP-BTH1/CdS and DPP-BTH2/CdS nanowire photoelectrode under AM 1.5 G sun illumination exhibited power conversion efficiency of about 0.30 % and 0.45 %, respectively. The PCE is three and four-fold higher than that of bare CdS nanowire-based DSSC devices. These simple chromophores provide a promising perspective for next-generation photovoltaic devices to harvest sunlight efficiently.