电镀法制备超疏水性铜表面

在对天然荷叶表面观察的基础上,通过改变电流密度控制电镀层表面的形貌,制备出了仿荷叶结构的铜表面.随着电镀电流密度的逐渐增大,接触角先增大后减小,当电流密度为0.08 A/cm²时,镀层的表面结构与荷叶表面最接近,其疏水效果最好,接触角最大,达到了153.5°,滚动角为7.9°(小于10°).这种表面未经任何修饰就产生了超疏水性.这是处于Cassie模型的一种亚稳定状态,只要表面形貌特征满足一定条件,就可使水滴在亲水基体上处于Cassie模型的亚稳态,从而有可能产生疏水性甚至超疏水性.对亲水材料的疏水机理进行了探讨,这些结果对亲水基体上超疏水性表面的制备和现有疏水理论的理解具有一定的意义.

Preparation of superhydrophobic copper surfaces by electroplating

The structure of the natural superhydrohlbic surface, lotus leaf, was studied, which inspired the fabrication method of superhydrophobic surfaces. Various copper surfaces were fabricated in different current densities via electroplating. As the current density increased, the water contact angle (CA) increased first and then decreased. When the current density was about 0.08 A/cm², the electroplated copper surface which resembled the lotus leaf reached superhydrophobic state (CA=153.5°, SA (sliding angle) = 7.9°). The surface with lotus leaf structure is superhydrophobic without any surface modification. It-s suggested that this is a meta-stable state in Cassie state. As long as the surface structure is suitable, a hydrophobic surface could be gotten, or even superhydrophobic surface, on hydrophilic materials. The hydrophobic mechanism was also analyzed. The results widen the horizon of fabricating superhydrophobic surfaces on hydrophilic materials and give light to the existing popular theories.