Articolo in rivista, 2022, ENG, 10.1016/j.jelechem.2022.116352

Seawater-based electrolytes facilitate charge transfer mechanisms improving the efficiency of dye-sensitized solar cells

Sangiorgi N.; Sangiorgi A.; Sanson A.

Institute of Science and Technology for Ceramics, National Research Council of Italy (ISTEC-CNR), Via Granarolo 64, Ra, Faenza, 48018, Institute of Science and Technology for Ceramics, National Research Council of Italy (ISTEC-CNR), Via Granarolo 64, 48018 Faenza, Ra, Italy, Italy; Institute of Science and Technology for Ceramics, National Research Council of Italy (ISTEC-CNR), Via Granarolo 64, Ra, Faenza, 48018, Institute of Science and Technology for Ceramics, National Research Council of Italy (ISTEC-CNR), Via Granarolo 64, 48018 Faenza, Ra, Italy, Italy

In this work, dye-sensitized solar cells containing seawater-based electrolytes were realized and investigated. The influence of the seawater composition on the electrochemical properties of the iodide/triiodide redox mediator was determined. High triiodide diffusion coefficient and ionic conductivity were assessed for seawater electrolytes through cyclic and linear voltammetry and impedance spectroscopy. Moreover, a notable influence of the seawater electrolyte on the charge transfer mechanism at the photoanode/dye/electrolyte interfaces was observed and deeply discussed. The ions, naturally present into seawater, reduce the charge recombination mechanism at the photoanode/electrolyte interface and promote a downward shift of the TiO conduction band, thus increasing the final DSSC efficiencies of 23% if compared with traditional devices containing water. The best seawater-based solar cell provides a photo-electrical conversion efficiency equal to 0.37% with 1.09 mA cm as short circuit current density. To the best of our knowledge, this is the first time that seawater is used as a key component for an energy production technology and the obtained results show the great potentiality of this green and recyclable element.

Journal of electroanalytical chemistry (1992) 915

Keywords

Seawater electrochemistry, Charge transfer reactions, Water-based electrolytes, Natural ions, Dye-Sensitized Solar Cells, Photoelectrochemical devices

CNR authors

Sanson Alessandra, Sangiorgi Alex, Sangiorgi Nicola

CNR institutes

ISTEC – Istituto di scienza e tecnologia dei materiali ceramici