-疏水材料--超疏水.ppt

LOGOSupperrepellentmaterial.1WettabilityvYoungsequation:cos=(SVSL)/LVvHydrophobic:90;vHydrophilic：90.Wettabilityisafundamentalpropertyofmaterialsurfaces.v Watercontactangle(WCA)largerthan150andextremelylowWCAhysteresisorslidinganglelessthan10.Superhydrophobicity.Slidinganglevmg(sin)/=(cosa-cosr)vaAdvancingcontactangle,vrRecedingcontactangle,vm-Thequalityofwaterdrop，vg-Accelerationofgravity，v-Diameterofwaterdrop，v-SurfaceEnergyofwaterdrop。vm，g，areconstant，then：vsin cosacosr.A.Watercollectorinthedesert.AntifoulingcoatingvTheundesirableaccumulationofmicroorganisms,plants,andanimalsonartificialsurfacesimmersedinseawater.vHighfrictionalresistanceandfuelconsumption,duetogeneratedroughness,vDeteriorationofthecoatingsothatcorrosion,discolouration,.vLowsurfaceenergycoatingformitigatingmarinebiologicalfoulingvAntifoulingcoating.Dragreduction.Self-cleaningmaterials.Antifrost.A.局部局部放大放大Oilwaterseparation.Supperrepellentmaterialinnature.出淤泥而不染，出淤泥而不染，濯清涟而不妖。濯清涟而不妖。-宋宋.周敦颐周敦颐爱莲说爱莲说.超疏水的荷叶和表面结构（超疏水的荷叶和表面结构（a)a)球形的水滴滴在荷叶表面（球形的水滴滴在荷叶表面（b)b)荷叶表面大荷叶表面大面积的微结构（面积的微结构（c)c)荷叶表面单个乳突（荷叶表面单个乳突（d d）荷叶表面的纳米结构）荷叶表面的纳米结构Lotuseffect.Cicadas wingsCicadas wingsv蝉翼表面由规则排列的纳米柱状结构组成纳米柱的直径大约在蝉翼表面由规则排列的纳米柱状结构组成纳米柱的直径大约在80 80 nmnm，纳米柱的间距大约在，纳米柱的间距大约在180 nm180 nm规则排列纳米突起所构建的粗糙规则排列纳米突起所构建的粗糙度使其表面稳定吸附了一层空气膜，诱导了其超疏水的性质，从而度使其表面稳定吸附了一层空气膜，诱导了其超疏水的性质，从而确保了自清洁功能。确保了自清洁功能。.Butterfly wingsButterfly .2、ThetheoreticsofSupperrepellentmaterialWettabilityCassiemodelWenzelmodelYoungsequation.vFor smooth,flat,uniform solid surface,the relationship between contact angle and surface energy can be described by Yongs equation(Thomas Young,1805):cos=(SV SL)/LV Interfacial tension:SV、SL、LV Yongsequation.Hydrophobic surfacevThe surface free energy of materials is The surface free energy of materials is related to the species and the related to the species and the concentration of the functional concentration of the functional surface groupssurface groups.Functional surfaceHydrophilic groups:OH、CHO、COOH、NH2Hydrophobic groups：CnH2n+1、CH=CH2、C6H5、X、NO2 CF3.FluorinatedpolymervCHCH2 2(36 dyn cm(36 dyn cm-1-1)CH)CH3 3(30 dyncm(30 dyncm-1-1)CF CF2 2(23 dyn cm(23 dyn cm-1-1)CF)CF3 3(15 dyn cm(15 dyn cm-1 1)The reason of choosing fluorosiliconeLow surface energy and high surface-active of CF3 groupImproves the adhesion and compatibility.self-assembly.vFor smooth,flat,uniform solid surface,the highest contactangleisonly119。.Real solid surface with concave-convex structureWenzel modelCassie model.LOGOCos*=r COS Wenzelmodel：.Cos*=r COS Providing=110，ifr0.53，*will be larger than 150Wenzelmodel.Cassiemodel.LOGOCos=fcos+(1-f)cos180=fcos+f-1Areafractionf=a/(a+b)lets assume that =110，if f is less than 0.2,will be larger than 150.CassiemodelProvidingCAbetweenliqiudandairis180.PAN Nano fiber materialPAN Nano fiber material.Self-cleaningeffectD.Roughening a hydrophobic materialFabrication3、ThefabricationofSupperrepellentsurfaceModifying a rough surfaces chemical components.Turning a Surface Super-Repellent Even to Completely Wetting Liquids Tingyi“Leo”Liu,etal.,Science,vol.346,pp.1096-1100,.Templatemethod.Etching.vMcCarthyMcCarthy等在聚四氟乙烯等在聚四氟乙烯 (PTFE)(PTFE)存在下存在下,用射频等离子体刻蚀聚丙烯用射频等离子体刻蚀聚丙烯 (PP)(PP)制备出粗糙表面。表面与水的前进角制备出粗糙表面。表面与水的前进角/后退角可达后退角可达 A/R=172/169。利用射频等离子体刻蚀法在不同刻蚀时间得到的聚丙烯扫描电子形貌图利用射频等离子体刻蚀法在不同刻蚀时间得到的聚丙烯扫描电子形貌图:(a)0 min,(b)30 min,(c)60 min,(d)90 min,(e)120 min,(f)180 min.ChenChen等利用纳米球刻蚀的方法首先得到了排列整齐的单层聚苯乙烯等利用纳米球刻蚀的方法首先得到了排列整齐的单层聚苯乙烯 (PS)(PS)纳米纳米珠阵列珠阵列 ,再用氧等离子体处理以进一步减小纳米珠的尺寸从而得到粗糙表面。再用氧等离子体处理以进一步减小纳米珠的尺寸从而得到粗糙表面。在其表面覆盖在其表面覆盖 20nm20nm厚的金膜并用十八硫醇厚的金膜并用十八硫醇(ODT)(ODT)进行修饰可以增强其疏水性。进行修饰可以增强其疏水性。通过调整通过调整 PSPS纳米珠的直径纳米珠的直径 (440-190 nm)(440-190 nm)可以控制表面接触角的大小可以控制表面接触角的大小 (132-168(132-168)。氧等离子体处理后的超疏水氧等离子体处理后的超疏水 PSPS纳米珠阵列表面纳米珠阵列表面.Chemicalvapordeposition 江江雷雷等等利利用用化化学学气气相相沉沉积积法法(CVD)在在石石英英基基底底上上制制备备了了各各种种图图案案结结构构的的阵阵列列碳碳纳纳米米管管膜膜,结结果果表表明明,水水在在这这些些膜膜表表面面的的接接触触角角都都大大于于 160,滚滚动动角角都都小小于于5,纳纳米米结结构构与与微微米米结结构构在在表表面面的的阶阶层层排排列列被被认认为为是产生这种高接触角、低滚动角的原因。是产生这种高接触角、低滚动角的原因。.4ResearchplanvInordertofabricatesuperhydrophobicorsuperhydrophilicsurfacesbasedonsub-micronstructures,IthinkmyresearchinUW.vFirstly,thefabricationofartificialstructuredsurface.vSeveralartificialstructuredsurfaceshavebeendisgined.vIfthesenanopillarandmushroomshapednanopillarsarraywithpieceof10mm10mmcanbepreparedbyelectroplatecopperornickelnanopillars?.vSecondly,.vLastly,thefabricationofhierarchicalstructures.Ifthepropertyofabovestructuredsurfaceaftersurfacefluorinationcannotmeetsuperhydrophobicorsuperhydrophilicrequirement,I.SomequestionsvExperimentrigandseveralapparatusanddevices,includingelectric-heatedthermostaticwaterbath,spincoating,ovenandsoon.vForcharacterization,SEM,contactanglemeterandXPS.LOGO.