Morphology study of nanoporous black TiOx synthesized by laser‐based method

In this work, we analyse and discuss the morphology evolution of black TiOx film formed on the surface of a titanium foil following the 1064 nm wavelength nanosecond pulsed laser irradiation in water. The nanostructure of the film depends on the number of laser pulses N and laser fluence F. We interpreted the experimental observations in terms of accumulated fluence FA, obtained as the product of N and F. We showed that the nanoporous morphology of this material occurs above a specific FA threshold of about 100 J/cm−2.