第六章疏水材料--超疏水知识发现

1、logo supperrepellent material1学习园地1 wettabilityvyoungs equation: cos=(sv sl)/ lv v hydrophobic: 90 ;v hydrophilic： 90 . wettability is a fundamental property of material surfaces2学习园地学习园地v water contact angle (wca) larger than 150 and extremely low wca hysteresis or sliding angle less than 10.superh

2、ydrophobicity3学习园地学习园地sliding anglevmg(sin)/ = (cosa-cosr)va advancing contact angle,vr receding contact angle, vm-the quality of water drop，vg-acceleration of gravity ，v-diameter of water drop，v-surface energy of water drop。vm，g， are constant ，then：vsincosa cosr.4学习园地学习园地a wide spectrum of applicat

3、ions5学习园地学习园地soysauce6学习园地学习园地7学习园地学习园地8学习园地学习园地water collector in the desert9学习园地学习园地 10学习园地学习园地antifouling coatingv the undesirable accumulation of microorganisms, plants, and animals on artificial surfaces immersed in sea water.v high frictional resistance and fuel consumption, due to generated r

4、oughness,v deterioration of the coating so that corrosion, discolouration, and alteration of the electrical conductivity of the material are favoured.11学习园地学习园地 vlow surface energy coatingfor mitigating marine biological foulingv antifouling coating12学习园地学习园地drag reduction13学习园地学习园地14学习园地学习园地self-cl

5、eaningmaterials15学习园地学习园地antifrost16学习园地学习园地antifogging surfaces17学习园地学习园地局部局部放大放大oilwater separation18学习园地学习园地supperrepellent material in nature19学习园地学习园地出淤泥而不染，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20学习园地学习园地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

6、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lotus effect21学习园地学习园地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 nm80 nm，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，从而确保了自清洁功能。，从而确保了自清洁功能。22学习园地学习园地butter

7、fly wingsbutterfly wings23学习园地学习园地24学习园地学习园地2、 the theoretics of supperrepellent materialwettabilitycassie modelwenzel modelyoungs equation25学习园地学习园地v for smooth, flat, uniform solid surface, the relationship between contact angle and surface energy can be described by yongs equation (thomas young,

8、1805 ) : : cos=(sv sl)/ lv interfacial tension: sv 、 sl 、 lv yongs equation26学习园地学习园地27学习园地学习园地functional surfacehydrophilic groups: oh、cho、 cooh、nh2hydrophobic groups： cnh2n+1、 ch=ch2、 c6h5、x、no2 cf328学习园地学习园地fluorinated polymer the reason of choosing fluorosilicone low surface energy and high surf

9、ace-active of cf3 group improves the adhesion and compatibility29学习园地学习园地self-assembly 30学习园地学习园地vfor smooth, flat, uniform solid surface, the highest contact angle is only 119。31学习园地学习园地real solid surface with concave-convex structurewenzel modelcassie model32学习园地学习园地logocos*= 1real contact areaapp

10、arent contact arrealvslsv ) -r(=r cos wenzel model：33学习园地cos*=lvslsv ) -r(=r cos providing =110，if r0.53， * will be larger than 150wenzel model34学习园地学习园地cassie model35学习园地学习园地logocos= fcos+(1-f)cos180 = fcos+f-1area fraction f=a/(a+b)lets assume that =110，if f is less than 0.2, will be larger than 1

11、50.cassie modelproviding ca between liqiud and air is 18036学习园地pan nano fiber materialpan nano fiber material37学习园地学习园地wenzel modelincreasing the contact area between liqiud and solidsliding angle very largecassie modeldecreasing the contact area between liqiud and solidsliding angle very small38学习园

12、地学习园地self-cleaning effectdirt39学习园地学习园地higher casmaller sasupperrepellent surface40学习园地学习园地roughening a hydrophobic materialfabricationsupperrepellent surfacemodifying a rough surfaces chemical components41学习园地学习园地turning a surface super-repellent even to completely wetting liquids tingyi“leo”liu,et

13、al.,science, vol. 346, pp.1096-1100, 2014. 42学习园地学习园地template method43学习园地学习园地etching 44学习园地学习园地 v mccarthymccarthy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

14、扫描电子形貌图: ( a) 0 min, ( b) 30 min, ( c) 60 min, ( d) 90 min,( e) 120 min, ( f) 180 min45学习园地学习园地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

15、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-(132-168168 ) )。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46学习园地学习园地47学习园地学习园地chemical vapor deposition 江雷等利用化学气相沉积法江雷等利用化学气相沉积法(cvd)在石英基底上制备了各种图案在石英基底上制备了各种图案结构的阵列碳纳米管膜结构的阵列碳纳米管膜, 结果表明结果表明, 水在这些膜表面的接触角

16、都大于水在这些膜表面的接触角都大于 160, 滚动角都小于滚动角都小于5, 纳米结构与微米结构在表面的阶层排列被认纳米结构与微米结构在表面的阶层排列被认为是产生这种高接触角、低滚动角的原因。为是产生这种高接触角、低滚动角的原因。48学习园地学习园地4 research planvin order to fabricate superhydrophobic or superhydrophilic surfaces based on sub-micron structures, i think my research in uw can be divided into three stages.4

17、9学习园地学习园地vfirstly, the fabrication of artificial structured surface. vseveral artificial structured surfaces have been disgined. vif these nanopillar and mushroom shaped nanopillars array with piece of 10 mm10 mm can be prepared by electroplate copper or nickel nanopillars?50学习园地学习园地51学习园地学习园地vsecon

18、dly, modify its components by surface fluorination. 52学习园地学习园地vlastly, the fabrication of hierarchical structures. if the property of above structured surface after surface fluorination can not meet superhydrophobic or superhydrophilic requirement, i will increase surface roughness by preparing hierarchical structures on above ar