【作者】 李晶；

【导师】 任露泉；

【作者基本信息】 吉林大学 ， 仿生科学与工程， 2012， 博士

【摘要】 疏水，特别是超疏水表面以其优异的憎水性在自清洁材料、微流体装置以及生物材料等许多领域有着重要的应用前景，倍受广泛关注。人们已经制备出许多人工疏水表面。金属材料在工业生产上和日常生活中越来越显示其重要性。因此，在具有高表面能的金属或合金基体上构建疏水表面成为近年来一个新兴领域和研究热点。本文从仿生学角度出发，基于耦合仿生理论，采用多种方法在铝合金和铜表面制备了疏水表面。进一步验证了固体表面的疏水性取决于表面形态、微-纳复合结构及化学组成的三元耦合。具体主要研究工作如下：1、选取典型荷叶为生物原型，通过激光扫描共聚焦显微镜（LSCM）、扫描电子显微镜(SEM)和X射线光电子能谱仪(XPS)对比观察分析了荷叶上、下表面的微观形貌、组织结构和化学成分。结果表明，荷叶上、下表面的化学成分相近，即覆盖一层蜡纸晶粒，而不同的是荷叶上表面由于存在微米级乳突形态和乳突上分布若干纳米绒突形成的复合结构，其疏水性强于只有单一“网格”状微观形态的下表面。模拟荷叶这一现象，建立了两种金属表面仿生耦合疏水模型，即由非光滑微形态、微-纳复合结构和低能材料三元耦合的仿生模型和微米形态与微-纳复合结构二元耦合的仿生模型。2、在仿生铝合金表面，采用硬质阳极氧化技术和分子自组装法制备了仿生耦合超疏水表面。利用LSCM、SEM和接触角测量仪对仿生氧化铝表面进行了表征。结果表明，仿生氧化铝表面形成了由较小微米尺度的氧化铝团聚体组成的凸凹不平的“小山丘”形态和微-微复合结构。其表面水接触角从小于90°提到约137°，而未低能化处理实现了金属表面由亲水到疏水的转变。继而采用分子自组装法，用十八烷基硫醇进行修饰，使仿生氧化铝表面获得了150±2°的超疏水特性。3、通过碱性湿化学刻蚀及其与阳极氧化相结合的方法对铝合金表面进行仿生疏水处理。利用LSCM、SEM、FESEM、XPS和接触角测量仪对仿生疏水表面进行了表征。结果表明，碱刻蚀铝表面获得了微米级非光滑形态，其水接触角平均增加到约118ｏ；而由碱刻蚀与阳极氧化相结合方法制备的氧化铝表面，同时获得了微观非光滑形态和微米级凹凸不平与纳米级的团簇凸包及孔洞构成的复合结构，其水接触角达到约148ｏ，未经低能化处理，获得与荷叶下表面非常接近的表面形貌和疏水特性。4、通过电沉积技术与低温氧化法结合，在碳钢基体上制备了复合铜薄膜，获得水接触角约150ｏ的超疏水特性。通过LSCM、SEM、XPS和接触角测量仪对复合铜薄膜表面进行了表征。结果表明，经上述方法处理后，碳钢表面形成了具有由大纳米尺度（500nm-1μm）的球状单体构成的类乳突状团簇体，和团簇体与团簇体之间的小纳米尺度的空隙构成的微-纳复合结构的仿生耦合铜薄膜。这种仿生耦合铜薄膜的形态和结构使其具有与荷叶上表面接近的粗糙度和疏水特性，水接触角接近150ｏ。5、基于生物耦合及其仿生原理与规律，提出金属表面构建多元耦合仿生疏水特性机制，并揭示出其共性规律，实现高能表面从亲水到疏水的转变。更多还原

【Abstract】 Hydrophobic and super-hydrophobic surfaces have considerable technological potentialfor various applications ranging from self-cleaning materials to microfluidic devices andbiomaterials due to their extremely good water-repellent properties. A number of studieshave been carried out to produce artificially bionic roughness-induced hydrophobic surfaces.Especially, more and more attention on hydrophobic properties in metal and alloy materialswith high surface energy were arose up because of their great importance in daily life as wellas in various industrial and biological applications such as self-cleaning characteristics.Therefore, building a hydrophobic surface on the metal or alloy substrate with high surfaceenergy become an emerging area in recent years and research focus. The wettability of metaland alloy surfaces depends strongly on multi-coupling of microscopy and/or microstructureand chemical composition of solid surface. Based on the bionics coupling theory, the thesisis engaged to reparation and research of bionic coupling hydrophobic surfaces in aluminumalloy and steel materials by using a variety of experimental methods. The main work of thethesis is listed as following:1、The resultant surfaces of lotus leaves were characterized by means of scanningelectron microscopy (SEM), laser scanning confocal microscopy (LSCM), x-rayphotoelectron spectrograph (XPS) and water contact angle measurements (WCA). Theresults show that the chemical composition of the surface of lotus leaves covered with alayer of waxy grain is much similar to their converse surfaces, and the difference is that thelotus leaves surface micro/nanostructure with micron mastoid morphology and a number ofnano-velvet mastoid is main factor affecting the wettability on the converse surface onlywith a single terrace-like morphology of lotus leaves. Based on the phenomenon of lotus leaves, the two models were established for coupling bionic hydrophobicity. The one iscomposed of non-smooth morphology, microstructure and low-energy materials, and theother is composed of micro morphology and micro/nano composite structure.2、Bionic alumina samples were fabricated on convex dome type aluminum alloysubstrate by using a hard anodizing technique. The resultant surfaces were characterized bymeans of scanning electron microscopy (SEM), laser scanning confocal microscopy (LSCM)and water contact angle measurements (WCA). The measurement of the wetting propertyshowed that the water contact angle of the unmodified as-anodized alumina bionic samplesincreases from90°to137°with increasing anodizing time. The increased water contractangle with anodizing time arises from the gradual formation of the hierarchical structure orcomposite structure. The structure is composed of the micro-scaled alumina columns andpores and the change in the height of columns and the depth of pores. The water contactangle increases significantly from96°to152°when the samples were modified withself-assembled monolayer of octadecanethiol (ODT), showing a change in the wettabilityfrom hydrophobicity to super-hydrophobicity.3、A hydrophobic surface was fabricated on etched aluminum alloy by using a hardanodizing technique. The resultant surfaces were characterized by means of scanningelectron microscopy (SEM), field scanning electron microscopy (FESEM), x-rayphotoelectron spectrograph (XPS), laser scanning confocal microscopy (LSCM) and watercontact angle measurements (WCA). The results show that cater-like pits and submicronporous aluminum films constitute a hierarchical rough aluminum surface after etching andsubsequent anodizing treating. The hierarchical micro/nanostructure exhibits excellenthydrophobic properties with water contact angles of about148ｏ. And, the etchedaluminum alloy substrate exhibits hydrophobic properties with water contact angles of about118ｏ. Without the low-energy treatment, the coupling surface gets very close surfaceroughness and hydrophobicity with the same as the lotus leaf lower surface.4、A electrochemical deposition process and thermal oxidation technology were used to fabricate rough surfaces and obtain excellent hydrophobic with an average water contactangle of150°on polycrystalline carbon steel substrates. The resultant surfaces werecharacterized by means of scanning electron microscopy (SEM), x-ray photoelectronspectrograph (XPS), laser scanning confocal microscopy (LSCM) and water contact anglemeasurements (WCA). The results show that the uniformity distributed micrometer-scalecauliflower clusters bodies were found to be consist of further nanometer scale oxidizedcopper spherical monomer on the oxidized copper substrate. This special structure is muchsimilar to that of the lotus leaf. The oxidized copper film with the hierarchicalmicro/nanostructure exhibits excellent super-hydrophobic properties with water contactangle of about150°.5、Based on the biological coupling and its bionic principles and laws, multi-couplingbionic hydrophobic characteristics mechanism on metal surface are proposed and thecommon law are revealed, to achieve the transformation of high-energy surface fromhydrophilic to hydrophobic.更多还原