Fabrication of a dye-sensitized solar cell containing a noncarboxylated spiropyran-derived photomerocyanine with cyclodextrin

Abstract

Abstract The fabrication, photovoltaic conversion, and photo-response of dye-sensitized solar cell (DSSC) containing a noncarboxylated spiropyran 1,3,3-trimethylindolino-β-naphthopyrylospiran ( 1 ) and carboxymethyl-β-cyclodextrin sodium salt (CM-β-CD) were investigated for the first time. In fact, we found the adsorption of photomerocyanine form (PMC) of 1 and inclusion complexes between the PMC and CM-β-CD (PMC/CM-β-CD) to the TiO 2 surface. The formation of PMC/CM-β-CD was confirmed by fluorescence spectroscopy. The incident photon-to-current conversion efficiency (IPCE) of the PMC-containing DSSC obtained 4.1% under 570-nm light irradiation, and the highest IPCE reached 11.1% by inclusion effect of CM-β-CD. Similar, the fillfactor and the open-circuit voltage were improved by CM-β-CD layer. The IPCE value of PMC/CM-β-CD-containing DSSC was decreased by visible light treatment, and it was considered that decrease of IPCE values are attributed to the formation of PMC isomer. Therefore, we demonstrated the photovoltaic conversion and photoresponsivity of the DSSC by incorporating a noncarboxylated PMC with inclusion effect of CM-β-CD layer.