Synthesis of cobalt oxides modified with palmitic acid and acetic acid and their application as a hydrophobic and self-cleaning coating

In the present research work, at first, the preparation of cobalt oxide nanoparticles was done by sol–gel auto-combustion method. The characteristic properties of the powder were done by techniques of XRD, FT-IR, AFM and FESEM techniques, which revealed the structural, functional groups and particle size and morphology of the sample, respectively. X-ray diffraction show formation of the Co3O4 nanoparticles with spinel structure. The average crystallite size of the sample was obtained 5-10 nm by using the Scherrer formula, respectively. FT-IR spectrum confirm the formation of cobalt oxide bonds. FESEM images show that the shape and size of nanoparticles produced by a sol – gel were 20-50 nm with a cuboid particle shape. After preparation of cobalt oxide nanoparticles, we used them to produce super-hydrophobic surface. The produced cobaltite nanoparticles were coated on the glass substrate and then put in the furnace. In the end, Palmitic acid and Acetic acid as samples of organic acids were applied for modification of coating.. Different ratio of the acides were used to prepare the coating. The best super hydrophobic coating was resulted for the coating modified with the 1:1 ration of palmetic acid and acetic acid. The value of contact angle (CA) for the water droplet on the surface of best coating was 158.2, indicating that the coating exhibit the super-hydrophobicity property. The self-cleaning property of the coating was tested by dispersing of mud on it for 48 h and after that no mud adhesive on the coating, indicating the self-cleaning properties of the modified cobaltite coating.