  Highly controlled coating of biomimetic polydopamine (PDA) was achieved on
titanium dioxide nanotubes (TiO2 NTs) by exposing TiO2 NT arrays to a slightly
alkaline dopamine solution. The thin films act as photonic sensitizers
(enhancing photocurrents and photodegradation) in the visible light range. The
PDA coatings can furthermore be used as a platform for decorating the TiO2 NTs
with different co-catalysts and metal nanoparticles (NPs).
