Abstract
Spray coating of a lead xanthate precursor on titanium dioxide surfaces has been carried out to deposit uncapped lead sulfide (PbS) nanocrystals. Cosensitizing N719 dye with resulting PbS nanocrystals in dye-sensitized solar cells demonstrates marked efficiencies up to 7.9%, an improvement of 29% compared with the absence of a cosensitizer. In this case, most of the absorbed light is involved in the photocurrent generation, confirmed by an incident photon-to-current conversion efficiency analysis, which is also in line with the ultraviolet-visible absorption spectra of these photoanodes. An increased precursor concentration has the negative effect on the power conversion efficiencies, primarily due to the blocking of incident light reaching the photosensitizer.