A low cost and facile preparation of hydrophobic silica films and powders by a solution-based process.

Autor: Tian, Tian, Tao, Haizheng, Xiao, Jing, Xu, Xingyi, An, Jiming
Zdroj: Journal of Wuhan University of Technology; Jun2015, Vol. 30 Issue 3, p489-493, 5p
Abstrakt: Super-hydrophobic surfaces with water contact angle (WCA) higher than 150° generated a lot of interests both in academic and in industry because of their self-cleaning functionality. Emphasis was given to the effect of pH value on the hydrophobic behavior of the obtained films or powders. At first, SiO sols were prepared by diluted ammonia. We found that following the increase of pH value of sol from 8 to 9, WCAs of the obtained films increased from 121.8° to 131.8°. Following the continued increase of the pH value of sol, precipitates began to appear and smooth film could not be obtained. The WCAs of the obtained powders could reach 121.7°, and through modifying by TMCS could further increase to as high as 165° and the water sliding angle (WSA) was 2°. The results of SEM indicate that the hydrophobic properties of the powders without modifying by TMCS should be originated from the formation of nano/micron binary structure, i e, a micron-scale diameter and a nano-scale surface roughness. In this work we provide a better solution to fabricate super-hydrophobic silica coating surface with a simple method at low cost. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index