title: Control of nanogeometry for advanced energy applications.
abstract: Incorporation of one-dimensional, large-surface-area, conductive nanofibers such as carbon nanotubes or 8 nm diameter TiO2 nanotubes into the dye-sensitized solar cell (DSSC) photo-anodes made of spherical TiO2 nanoparticles is shown to significantly improve the photocurrent density and the energy conversion efficiency. The observed DSSC solar cell efficiency enhancement in the presence of elongated nanoscale elements is attributed primarily to the reduction in microcracking tendency of the anode layer and associated robust electron transport, although some contributions of the electrical conducting nature of the filler material may also be possible. A use of metallic conduction paths such as embedded Ti-coated stainless steel mesh screen in the TiO2 anode layer is also described for enhanced photoanode constructions with a future possibility of FTO (fluorinated tin oxide)-glass-free DSSC. It is also shown that the control of contact resistance during DSSC assembly and electrical connection is an important aspect for more accurate evaluations of DSSC performance.
authors.affiliation: Materials Sciences and Engineering, University of California at San Diego, La Jolla, CA 92093, USA.
authors.forename: Jirapon
authors.initials: J
authors.lastname: Khamwannah
authors.forename: Hyunsu
authors.initials: H
authors.lastname: Kim
authors.forename: Yan Yan
authors.initials: YY
authors.lastname: Zhang
authors.forename: Tae Kyoung
authors.initials: TK
authors.lastname: Kim
authors.forename: Sungho
authors.initials: S
authors.lastname: Jin