Modification Of Copper Mesh To Achieve Superhydrophobic Surface

Modification of copper mesh to achieve a superhydrophobic surface has been presented in this thesis. A superhydrophobic copper mesh has been fabricated by immersing copper mesh in an aqueous solution consisting of ammonium persulfate ((NH4)2S2O8) and sodium hydroxide (NaOH) followed by treatment with stearic acid, a non-toxic, inexpensive and readily available low surface energy material. The combined effects of rough copper(II) hydroxide (Cu(OH)2) micro-nano structures and coating with low surface energy stearic acid molecules were ascribed to the resulting superhydrophobic copper mesh surface. The modification was carried out under different ammonium persulfate concentration, stearic acid concentration and mesh number. It was found that the modified mesh with 500 and 2000 mesh number exhibited superhydrophobicity, with a water contact angle of 162.7° and 159°, respectively for 0.5 M (NH4)2S2O8. Besides, the surface of the Cu(OH)2 nanoneedles modified with 0.006 M stearic acid showed a water contact angle of 152.7° which indicated superhydrophobicity. Higher stearic acid concentration caused the stearate crystals deposited onto the mesh surface. The prepared samples were characterized by using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR) techniques. The surface morphologies, crystal structures, surface chemical elements and static water contact angles of the Cu(OH)2 coatings were studied in detail