Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Preparation and characterization of superhydrophobic surfaces based on hexamethyldisilazane-modified nanoporous alumina | Tasaltin et al. Nanoscale Research Letters 2011 6 487 http content 6 1 487 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access Preparation and characterization of superhydrophobic surfaces based on hexamethyldisilazane-modified nanoporous alumina 1 2 1 1 2 Nevin Tasaltin Deniz Sanli Alexandr Jonas Alper Kiraz and Can Erkey Abstract Superhydrophobic nanoporous anodic aluminum oxide alumina surfaces were prepared using treatment with vapor-phase hexamethyldisilazane HMDS . Nanoporous alumina substrates were first made using a two-step anodization process. Subsequently a repeated modification procedure was employed for efficient incorporation of the terminal methyl groups of HMDS to the alumina surface. Morphology of the surfaces was characterized by scanning electron microscopy showing hexagonally ordered circular nanopores with approximately 250 nm in diameter and 300 nm of interpore distances. Fourier transform infrared spectroscopy-attenuated total reflectance analysis showed the presence of chemically bound methyl groups on the HMDS-modified nanoporous alumina surfaces. Wetting properties of these surfaces were characterized by measurements of the water contact angle which was found to reach 2 . The contact angle values on HMDS-modified nanoporous alumina surfaces were found to be significantly larger than the average water contact angle of 3 on smooth thin film alumina surfaces that underwent the same HMDS modification steps. The difference between the two cases was explained by the Cassie-Baxter theory of rough surface wetting. Keywords superhydrophobic surfaces surface modification hexamethyldisilazane nanoporous alumina Introduction Phenomenon of superhydrophobicity refers to the existence of very high water contact angles on solid surfaces contact angle 150 . This effect which was originally observed in nature . on lotus leaves is important for a wide range of scientific and technological .
