title: Enhanced photovoltaic properties and long-term stability in plasmonic dye-sensitized solar cells via noncorrosive redox mediator.
abstract: We demonstrate the localized surface plasmon resonance (LSPR) effect, which can enhance the photovoltaic properties of dye-sensitized solar cells (DSSCs), and the long-term stability of size-controlled plasmonic structures using a noncorrosive redox mediator. Gold nanoparticles (Au NPs) were synthesized with a phase transfer method based on ligand exchange. This synthetic method is advantageous because the uniformly sized Au NPs, can be mass produced and easily applied to DSSC photoanodes. The plasmonic DSSCs showed an 11% improvement of power conversion efficiency due to the incorporation of 0.07 wt % Au NPs, compared to the reference DSSCs without Au NPs. The improved efficiency was primarily due to the enhanced photocurrent generation by LSPR effect. With the cobalt redox mediator, the long-term stability of the plasmonic structures also significantly increased. The plasmonic DSSCs with cobalt(II/III) tris(2,2'-bipyridine) ([Co(bpy)3](2+/3+)) redox mediator maintained the LSPR effect with stable photovoltaic performance for 1000 h. This is, to our knowledge, the first demonstration of the long-term stability of plasmonic nanostructures in plasmonic DSSCs based on liquid electrolytes. As a result, the enhanced long-term stability of plasmonic NPs via a noncorrosive redox mediator will increase the feasibility of plasmonic DSSCs.
authors.affiliation: Photo-Electronic Hybrids Research Center, Korea Institute of Science and Technology (KIST) , Seoul 136-791, Korea.
authors.forename: Heesuk
authors.initials: H
authors.lastname: Jung
authors.forename: Bonkee
authors.initials: B
authors.lastname: Koo
authors.forename: Jae-Yup
authors.initials: JY
authors.lastname: Kim
authors.forename: Taehee
authors.initials: T
authors.lastname: Kim
authors.forename: Hae Jung
authors.initials: HJ
authors.lastname: Son
authors.forename: BongSoo
authors.initials: B
authors.lastname: Kim
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Doh-Kwon
authors.initials: DK
authors.lastname: Lee
authors.forename: Honggon
authors.initials: H
authors.lastname: Kim
authors.forename: Jinhan
authors.initials: J
authors.lastname: Cho
authors.forename: Min Jae
authors.initials: MJ
authors.lastname: Ko
keywords: cobalt-based electrolyte; corrosion; dye-sensitized solar cells; gold nanoparticles; localized surface plasmon resonance; long-term stability