Dip coating of Tungsten trioxide on a stainless steel

Thin films coating of molybdenum-doped tungsten trioxide (WO3-Mo) and tungsten trioxide (WO3) were produced from aqueous solutions on a stainless steel substrate using simple dip-coating technique and the 5th, 10th, and 15th film layers analyzed were continuous and homogeneous. The crystallinity and morphology of the films produced on the stainless steel surface depended on the concentration of the polyvinyl alcohol (PVA) in the aqueous solution and the metal cation species. From the analysis of the FE-SEM, spike-like nanostructures were revealed from the construction of the WO3 dip-coated film surfaces. From the measured values of the static water contact angle on the coated steel film surfaces indicated that the WO3 film deposited can possess both hydrophobic and hydrophilic behavior, whereas WO3-Mo films displayed hydrophilic character. The surface of coated steel samples held a lubricating layer that is significantly better than the original stainless steel samples, exhibiting a foremost reduction in wear and friction. Base on these outstanding thermal, hydrophobic and hydrophilic properties of WO3 and WO3-Mo coated films along with simple dip-coating method suggest a very auspicious ability in industrial usage.