title: Completely transparent conducting oxide-free and flexible dye-sensitized solar cells fabricated on plastic substrates.
abstract: To achieve commercialization and widespread application of next-generation photovoltaics, it is important to develop flexible and cost-effective devices. Given this, the elimination of expensive transparent conducting oxides (TCO) and replacement of conventional glass substrates with flexible plastic substrates presents a viable strategy to realize extremely low-cost photovoltaics with a potentially wide applicability. To this end, we report a completely TCO-free and flexible dye-sensitized solar cell (DSSC) fabricated on a plastic substrate using a unique transfer method and back-contact architecture. By adopting unique transfer techniques, the working and counter electrodes were fabricated by transferring high-temperature-annealed TiO2 and Pt/carbon films, respectively, onto flexible plastic substrates without any exfoliation. The fabricated working electrode with the conventional counter electrode exhibited a record efficiency for flexible DSSCs of 8.10%, despite its TCO-free structure. In addition, the completely TCO-free and flexible DSSC exhibited a remarkable efficiency of 7.27%. Furthermore, by using an organic hole-transporting material (spiro-MeOTAD) with the same transfer method, solid-state flexible TCO-free DSSCs were also successfully fabricated, yielding a promising efficiency of 3.36%.
authors.affiliation: ‡Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul, 120-746, Republic of Korea.
authors.forename: Kicheon
authors.initials: K
authors.lastname: Yoo
authors.forename: Jae-Yup
authors.initials: JY
authors.lastname: Kim
authors.forename: Jin Ah
authors.initials: JA
authors.lastname: Lee
authors.forename: Jin Soo
authors.initials: JS
authors.lastname: Kim
authors.forename: Doh-Kwon
authors.initials: DK
authors.lastname: Lee
authors.forename: Kyungkon
authors.initials: K
authors.lastname: Kim
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Kim
authors.forename: BongSoo
authors.initials: B
authors.lastname: Kim
authors.forename: Honggon
authors.initials: H
authors.lastname: Kim
authors.forename: Won Mok
authors.initials: WM
authors.lastname: Kim
authors.affiliation: ‡Department of Chemical and Biomolecular Engineering, Yonsei University, Seoul, 120-746, Republic of Korea.
authors.forename: Jong Hak
authors.initials: JH
authors.lastname: Kim
authors.forename: Min Jae
authors.initials: MJ
authors.lastname: Ko
keywords: TCO-free; dye-sensitized solar cells; flexible; plastic substrates; transfer method