Dye sensitized solar cells (DSSCs) offer an inexpensive alternative to conventional p-n junction solar cells on the market today.  The ruthenium-based N3 dye (Cis-bis(isothiocyanato)bis(2,2’-bipyridyl-4,4’-dicarboxylato)ruthenium(II)) has been one of the most efficient dyes in DSSC devices.  In a DSSC, N3 dye binds to the surface of a semiconductor via its carboxylic acid groups.  The binding mode at the interface directly affects the electronic coupling of the dye to the semiconductor, thus affecting the overall rate of electron transfer and efficiency of the device.  Heterodyne detected vibrational sum frequency generation (HD-VSFG) is used to investigate how the protonation state of the N3 dye may alter the binding geometry to a substrate.  The pH-dependence of the average orientation of N3 dye on gold is observed using HD-VSFG, additionally, integrated intensities from observed spectra reveal that the number of adsorbed N3 molecules is pH dependent.  The insight gained here will be useful in understanding the interfacial chemistry of dye molecules and semiconductor surfaces.<br/>

Using vibrational sum frequency generation to investigate the adsorption of N3 dye in different pH conditions

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.