Highly functional titania nanoparticles produced by flame spray pyrolysis : photoelectrochemical and solar cell applications

Nanoparticulate titania was synthesized by flame spray pyrolysis and was used to construct photoanodes for photoelectrochemical cells and quantum dot sensitized solar cells. Powders obtained by flame spray pyrolysis were composed of smaller nanoparticles and had higher specific surface areas than common commercial types of titania and this was carried over to the structure of the photoanodes and reflected on the photoelectrocatalytic and solar cell behavior of the photoanodes. The highest specific surface area and the smallest nanoparticle size produced in this work were 249 m2g-1 and 7 nm, respectively. CdS-sensitized photoanodes were affected by the amount of the deposited sensitizer, which was the largest in the case of the powder with the highest specific surface area. When, however, the photoanodes were loaded with a relatively large amount of CdSe sensitizer, the role of the latter increased and the differences between the different forms of titania diminished.