Fabrication of Hydrophobic ZnO Surfaces on SS304 Substarates

We have deposited undoped ZnO and 3% Al doped ZnO layers upon stainless steel (SS 304) substrates to study the hydrophobic nature of the surface. The ZnO layers were deposited at 673K by spray pyrolysis. Then the prepared films were annealed at various temperature like 723K, 773K, 873K and 973K. The structural and compositional analysis shows that the ZnO has a preferential growth along (002) planes. By contact angle measurement, it is revealed that annealed samples at 723K for both ZnO as well as 3% Al doped ZnO surfaces exhibits maximum contact angle of 120.59° and 125.97° respectively, which shows that the surfaces are hydrophobic. The photoluminescence spectra show that there are blue and green emission peaks in all samples. Thus, the hydrophobic ZnO thin films can be of great importance in commercial application as transparent self-cleaning surfaces.