Applications of P-Type NiO in Dye-Sensitized Solar Cells

This study investigates the applicability of p-type NiO in the working (or counter) electrode of a dye-sensitized solar cell (DSSC). The working electrode was designed and fabricated by depositing a film of TiO2/NiO composite particles, which were prepared by mixing the Ni powder with TiO2 particles using dry mixing method. The counter electrode was fabricated by depositing a NiO film on top of a Pt film, which has been deposited on a FTO glass using an ion-sputtering coater (or E-beam evaporator). This study shows that the power conversion efficiency of the DSSC with TiO2/NiO composite particles (3.80%) substantially exceeds that of the conventional DSSC (3.16%) due to the effects of the NiO barrier and the n-p junction. Aside from this, the power conversion efficiency of a DSSC with a Pt(E)/NiO counter electrode (4.28%) substantially exceeds that of a conventional DSSC with a Pt(E) counter electrode on which a Pt film was deposited using an E-beam evaporator. This result is attributed to the fact that the NiO film coated on the Pt(E) counter electrode improves the electrocatalytic activity of the counter electrode.