A novel titanium oxide paste based on the Pechini sol–gel method and nanocrystalline titanium oxide powder have been developed by Urša Opara Krašovec et al. at the University of Ljubljana in Slovenia.

Dye-sensitized solar cells (DSSCs) have been intensively studied and researched for the last decade as a promising third-generation solar cell technology, owing to their potential low-cost manufacturing based on printing technology. The photoactive electrode of a DSSC is a transparent conductive oxide (TCO) glass coated with nanoporous TiO₂ sensitized with dyes for visible light harvesting, while the counter electrode is a TCO glass coated with platinum.

Titanium oxide layers possess a high inner surface area, ensuring high dye loading and well connected nanocrystalline grains, and hence good electron transport within the layer. The dye-sensitized layers have been used to assemble dye-sensitized solar cells (DSSCs) with acetonitrile- and ionic liquid-based electrolytes. Overall conversion efficiencies of DSSCs determined under standard test conditions (100 mW/cm², 25°C and AM1.5G) are 10.2% for the acetonitrile electrolyte and 7.3% for the ionic liquid-based electrolyte.

The new work reports further improvement of the TiO₂ paste formulation by changing the molar ratio between the polyester and titanium isopropoxide. The TiO₂ layer morphology is presented with scanning electron micrographs, while their efficiency for DSSCs has been evaluated for ionic liquid- and acetonitrile-based electrolytes.

Solar Energy Materials and Solar Cells, Volume 93, Issue 3, March 2009, Pages 379–381.
DOI: 10.1016/j.solmat.2008.11.012