Porous TiO2 layer for dye-sensitized solar cell formed with non-equilibrium 2D plasma induced by dielectric barrier discharge under atmospheric pressure

Abstract

A non-equilibrium 2D plasma was induced on the insulating plate by a dielectric barrier discharge under a flowing mixture of nitrogen and oxygen gases. A titanium-peroxo precursor to prepare an anatase TiO2 film was irradiated with the plasma. The technique was applied to form a porous TiO2 layer for a dye-sensitized solar cell (DSSC). We found the N–O metastable plasma induced under the higher nitrogen gas concentration played an important role in forming a porous TiO2 layer and promoted a necking process between the TiO2 particles to reduce an internal resistance within the layer. The DSSC fabricated with the porous TiO2 layer showed maximum conversion efficiency of 3.7%, which was lower than that of the general DSSC. However, with a non-equilibrium 2D plasma, the substrate temperature was kept below 80 °C during the plasma irradiation, which opens the way for subsequent progress in producing a DSSC for daily use.