Effect of Acid Etching upon ZnO Anodes in Dye Sensitized Solar Cells

Solar cells must accomplish two basic tasks to generate current: absorb incident photons and conduct excited electrons to the circuit. Traditional solar cells made of silicon accomplish these with a single, expensive material. Dye sensitized solar cells (DSSC) are an alternative using separately optimized materials for each task. In short, a dye absorbs the photons and injects them into a semiconductor substrate which ferries the electrons into the circuit. An electrolyte containing a redox couple completes the circuit by reducing the oxidized dye. The best performing DSSCs contain a TiO2 nanoparticle (NP) anode sensitized by a ruthenium dye commercially known as N719; these have reached 12% efficiency.