title: Enhancement of Open Circuit Voltage of a ZnO-Based Dye-Sensitized Solar Cell by Means of Piezotronic Effect.
abstract: Two of the most known properties of ZnO were used to improve the performance of a dye-sensitized solar cell (DSSC) using a nanoadduct formed by zinc oxide and the well-known ruthenium dye N719. The wurtzite form of zinc oxide suffers from piezoelectricity and its energetic levels are very similar to those of the most used inorganic semiconductor employed in DSSCs, that is, TiO2 . We demonstrate that the synthesis of a ZnO@N719 nanoadduct does not affect the electronic communication between the inorganic semiconductor and the organic dye. The I-V characteristics in the dark and under illumination highlight a photoactivity of the ZnO@N719 active layer with values of Jsc , Voc and fill factor comparable to the data reported in the literature. When a mechanical strain is applied to the ZnO@N719 film, a piezopotential is recorded and it depends on the intensity of the applied pressure. According to the piezotronic effect, mechanical strain contributes to increase the open circuit voltage by about 14 %.
authors.affiliation: Department of Engineering for Innovation, University of Salento, S.P. 6, Lecce-Monteroni, 73100, Lecce, Italy.
authors.forename: Simona
authors.identifier: 0000-0002-5506-5413
authors.initials: S
authors.lastname: Bettini
authors.affiliation: Department of Engineering for Innovation, University of Salento, S.P. 6, Lecce-Monteroni, 73100, Lecce, Italy.
authors.forename: Rosanna
authors.initials: R
authors.lastname: Pagano
authors.affiliation: Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, S.P. 6, Lecce-Monteroni, 73100, Lecce, Italy.
authors.forename: Ludovico
authors.identifier: 0000-0002-6943-8647
authors.initials: L
authors.lastname: Valli
authors.affiliation: Department of Cultural Heritage, University of Salento, Via D. Birago, 64, 73100, Lecce, Italy. gabriele.giancane@unisalento.it.
authors.forename: Gabriele
authors.identifier: 0000-0001-5089-5429
authors.initials: G
authors.lastname: Giancane
keywords: piezopotential; piezotronics; ruthenium-based dyes; solar cells; zinc oxide