As shown in the figures above, the position of the dye layer on titania film can be controlled to effectively expand the spectral response of the solar cell. Specifically, the desorption depth can be directed by the number of repetitions of the desorption process.

In the study, the team was able to adjust the layer thickness to optimize the photocurrent. Additionally, dye layers of three and over can be stacked using this technique.

The researchers anticipate that the method will be widely available commercially due to its easy preparation and wide range of application.

Full details can be found in the journal Nanotechnology.