Flexible deposition of TiO2 electrodes for photocatalytic applications: Modulation of the crystal phase as a function of the layer thickness

TiO2 thin films for electrochemical applications (e.g., photocatalysis) may require a careful control of the crystalline phase and the surface morphology. Flexible radiofrequency magnetron sputtering deposition of TiO2 thin films (anatase, rutile or variable mixtures of the two polymorphs) onto Ti disks has been achieved by controlling the layer thickness at variable temperatures.This result is of great importance in view of the preparation of TiO2 electrodes for photo-catalytic applications. In principle, it allows to modulate the phases present in the active layer by changing the layer thickness even using different deposition temperatures, which also implies modification of the morphology of the layer, therefore addressing two major issues in the field of photocatalysis mediated by titanium dioxide.

Graphical AbstractC-AFM images (2×2 μm2) of TiO2 thin films deposited at 750 °C with different thicknesses: (a) 50 nm [Z=40 nm]; (b) 100 nm [Z=60 nm]; (c) 400 nm [Z=120 nm].Figure optionsDownload as PowerPoint slideHighlights
► TiO2 flexible deposition.
► Modulation of the crystal phase.
► Modification of the layer morphology.