Increasing the Efficiency of Dye-Sensitized Solar Cells by Adding Nickel Oxide Nanoparticles to Titanium Dioxide Working Electrodes

Abstract

In this study, nickel oxide (NiO) nanoparticles were added to a titanium dioxide (TiO2) nanoparticle paste to fabricate a dye-sensitized solar cell (DSSC) working electrode by using a screen-printing method. The effects of the NiO proportion in the TiO2 paste on the TiO2 working electrode, DSSC devices, and electron transport characteristics were comprehensively investigated. The results showed that adding NiO nanoparticles to the TiO2 working electrode both inhibited electron transport (a negative effect) and prevented electron recombination with the electrolyte (a positive effect). The electron transit time was extended following an increase in the amount of NiO nanoparticles added, confirming that NiO inhibited electron transport. Furthermore, the energy level difference between TiO2 and NiO generated a potential barrier that prevented the recombination of the electrons in the TiO2 conduction band with the I3- ions in the electrolyte. When the TiO2–NiO ratio was 99:1, the positive effects outweighed the negative effects. Therefore, this ratio was the optimal TiO2–NiO ratio in the electrode for electron transport. The DSSCs with a TiO2–NiO (99:1) working electrode exhibited an optimal power conversion efficiency of 8.39%, which was higher than the DSSCs with a TiO2 working electrode.

Mesoporous Metal Oxide Films

“…One of the most frequent uses of mesoporous metal oxide films is their use as working electrodes for the fabrication of dye-sensitized solar cells (DSSC). In this Special Issue, Tsai et al [15] added NiO nanoparticles to a TiO 2 paste and used a screen-printing method to make a composite film that could be used for the fabrication of a DSSC. The results showed that the addition of NiO nanoparticles to the TiO 2 working electrode inhibited electron transport and prevented electron recombination with the electrolyte.…”