Effect of substrate on improving the wettability properties of nickel oxide oblique columnar nanostructures by modifying the surface morphology

In this study, nickel oxide oblique columnar nanostructures were deposited on glass and steel substrates by physical evaporation deposition with oblique angle. The surface morphology, structural and wettability properties are affected by the substrate. XRD studies showed that the nanostructure deposited on steel has a better orientation than the nanostructure deposited on glass. AFM and FESEM studies showed that surface roughness and grain size depend on the type of substrate. The surface roughness of the nanostructure deposited on steel is higher compared to the nanostructure deposited on glass, and big grains are formed by the growth of small grains and merging them together. The grains size of the nanostructure deposited on steel are higher than the nanostructure deposited on glass. Contact angle measurements showed that the nanostructures deposited on glass and steel are hydrophilic and hydrophobic in nature with contact angles of 78 and 120, respectively. The morphology of the nickel oxide oblique columnar nanostructure surface deposited on steel causes to increase the contact angle of the water drop with the surface.