超疏水网状结构对水中气泡的转移作用

Bubble Transfer Effect of Superhydrophobic Mesh Structure in Water

通过一步浸泡法制得了超疏水网状结构.采用环境扫描电镜(ESEM)、X光电子能谱(XPS)和傅里叶变换红外光谱(FTIR)分别对超疏水网状结构的微观形貌和化学组成进行了表征,结果表明,超疏水的网状结构是由连续排列的类菊花状结构堆积而成的,组成花瓣的微簇是具有层状结构的Cu[CH3(CH2)12COO]2.借助高速照相机研究了超疏水网状结构表面与水中气泡的相互作用行为规律,发现该超疏水网状结构对水中气泡产生转移作用,而亲水的网状结构则不具备该特性.

Gas/liquid separation is a fundamental process in many chemical or biological processes,especially for microfluidic systems,in which microchannel can impede or even stop liquid flowing.Recently,many researches are focused on bubble removal from where they form in order to avoid the above adverse effects occurring.However,the introduction of venting holes will cause the leakage of inner liquid.Superhydrophobic mesh structures can hold water droplets steadily,and its capability of leakage prevention is excellent for mesh with small size.Herein,microscaled and nanoscaled hierarchical structured copper mesh was fabricated by one-step solution-immersion process and it exhibited perfect superhydrophobicity.The component and morphology of the as-prepared sample were characterized by XPS,FTIR and ESEM.FTIR and XPS spectra demonstrate that the aggregates have a chemical composition of Cu[CH3（CH2）12COO]2.The ESEM images clearly show that clusters of continuous flowerlike architectures are formed on the copper mesh substrate.Then,bubble behavior on such special structures was investigated by high-speed camera.It is found that bubbles in water can easily vent out through the superhydrophobic copper mesh,while the case does not happen to hydrophilic copper mesh.These findings will provide a method in designing novel superhydrophobic materials in the near future,which may be developed into an effective degassing plate with bubble capture and distributed venting for microfluidic devices.