writer：Zhang Yong,Pi Pihui,Wen Xiufang,Zheng Dafeng,Cai Zhiqi,Cheng Jiang
keywords：wettability gradient,contact angle hysteresis, surface tension, preparation,application
source：期刊
specific source：PROGRESS IN CHEMISTRY卷: 23 期: 12 页: 2457-2465
Issue time：2011年
A gradient wettability surface is the one that displays a gradual change in its surface tension along its length. The wettability of solid surfaces is governed by both the surface chemical composition and the geometrical microstructure. In this paper, two ways to fabricate the wettability gradient surfaces, controlling the chemical composition or surface morphology along the surfaces are introduced,and the application of the functional wettability surfaces, such as droplet moving, micro-fluid flow, and biosorption has been presented. The dominant force responsible for drop movement is the unbalanced Young force that results front the difference in wettability between the front and backsides of the drop, and the contact angle hysteresis has a reduced effect on the droplet moving. Generally speaking, the higher the gradient, the faster the droplet moved. The wettability gradient surfaces are also used for control of liquids flow on submillimeter scales. In addition, surface wettability is found to play an important role in biosorption and the difference in protein adsorption behavior can be attributed mainly to the wettability gradient and the type of protein. Problems existed in this research field and prospects of wettability gradient surfaces are also discussed briefly.