In this paper, we report on a novel material: nanostructured CdS:O film prepared at room temperature by rf sputtering, and its application in CdTe solar cells. The CdS:O film has a higher optical bandgap (2.5-3.1 eV) than the poly-CdS film and a nanostructure; the bandgap increases with an increase of oxygen content (from ~4 at.% to ~23 at.%) and a decrease of grain size (from about a few hundred Å to a few tenths Å). Our results have also demonstrated that the higher oxygen content presented in the nanostructured CdS:O films can significantly suppress the Te diffusion from the CdTe into the CdS film and the formation of a CdS 1-y Te y alloy with a lower bandgap that results in poor quantum efficiency in the shortwavelength region. The preliminary device results have demonstrated that the J sc of the CdTe device can be greatly improved by exploiting the thin nanostructured CdS:O film, while maintaining higher V oc and FF. We have fabricated a CdTe cell demonstrating an NREL-confirmed total-area efficiency of 15.5%.

This study indicates that children’s hands acquire substantial amounts of various phthalates. The levels measured in handwipes, although higher, are somewhat representative of levels on other body locations. Via dermal absorption, as well as hand-to-mouth activity, phthalates on hands and other body locations contribute to the overall body burden of these compounds. Dermal absorption from air and contact transfer from surfaces is expected to occur for many SVOCs commonly found indoors (e.g. bisphenols, synthetic musks, organophosphates). However, the dermal pathway has often been neglected in exposure assessments of indoor pollutants. Knowledge regarding phthalates and other SVOCs in handwipes can facilitate our understanding of risks and aid in the mitigation of adverse health effects resulting from indoor exposures. To make progress toward these goals, further studies are necessary, including investigations of phthalate level variability in skinwipes collected at different locations on the body and the impact of clothing on dermal absorption from air.