Hydrophobic surface by growing ZnO nanorods on zinc electroplated steel | |
| Author | Konakom Buayai |
| Call Number | AIT Thesis no.ME-09-07 |
| Subject(s) | Hydrophobic surfaces Zinc Electroplating |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Microelectronics, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ME-09-07 |
| Abstract | This thesis is intent to study hydrophobic surface of steel after depositing zinc by zinc electroplating technique and then growing ZnO nanorods by hydrothermal process. The best water contact angle (WCA) after growing ZnO nanorods is 117º. This surface can be improved by treatment with 1H, 1H, 2H, 2H-Perfluorooctyltriethoxysilane and the water contact angle reach 145º comparing with the water contact angle of a lotus leaf which is about 150º. The wear test is performed to find the minimum force that can wear ZnO nanorods. This force is 10 μ N. Normally steel has hydrophilic property (WCA < 90º). Then this steel is coated with zinc by simple and commercial method that is zinc electroplating. In this thesis, the thicknesses of zinc are varied from 10nm to 100nm. After zinc deposition, some zinc electroplated steel samples are baked at different high temperature, 150ºC and 250ºC, to create oxide for growing ZnO nanorods. Then zinc electroplated steel samples are immersed in the aqueous chemical composed of zinc nitrate hexahydrate (Zn(NO 3 ) 2 . 6H 2 O) and hexamethylenetetramine (Hexamine, C 6 H 12 N 4 ) for growing ZnO nanorods. Hydrothermal process is used during ZnO nanorods growing. Both zinc electroplated steel and chemical solution (precursor) are kept at 90ºC for 20 hours. The precursor is changed every 5 hours. The results are discussed in term of water contact angle in correlation with coated zinc thicknesses and temperature for baking zinc electroplated steel before growing ZnO nanorods. From the experiment, 50-70nm coated zinc thickness samples without baking before growing ZnO nanorods provide the best WCA at 117º. However, the water droplet can not roll on the samples due to high surface energy. So, the samples are treated with fluorine rich solution to reduce surface energy so that the water droplet can roll on the samples. |
| Year | 2009 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ME-09-07 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Industrial Systems Engineering (DISE) |
| Academic Program/FoS | Microelectronics (ME) |
| Chairperson(s) | Dutta, Joydeep |
| Examination Committee(s) | Krisda Siangchaew;Afzulpurk, Nitin V. |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship;NECTEC;Western Digital (Thailand) Co.,Ltd |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2009 |