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不锈钢网表面润湿性的调控及其油水分离性能

  • 李志文

    机 构：

    青岛理工大学 机械与汽车工程学院, 青岛 266520

    ×
  • ， 齐博浩

    机 构：

    青岛理工大学 机械与汽车工程学院, 青岛 266520

    ×
  • ， 刘长松

    机 构：

    青岛理工大学 机械与汽车工程学院, 青岛 266520

    ×
  • ， 赵欣生

    机 构：

    青岛理工大学 机械与汽车工程学院, 青岛 266520

    ×
  • ， 栗心明

    机 构：

    青岛理工大学 机械与汽车工程学院, 青岛 266520

    ×

青岛理工大学 机械与汽车工程学院, 青岛 266520；

Manipulation of Surface Wettability on Stainless Steel Mesh and Its Oil-Water Separation Performance

  • LI Zhiwen

    Affiliation：

    School of Mechanical & Automotive Engineering, Qingdao University of Technology, Qingdao 266520 , China

    ×
  • ， QI Bohao

    Affiliation：

    School of Mechanical & Automotive Engineering, Qingdao University of Technology, Qingdao 266520 , China

    ×
  • ， LIU Changsong

    Affiliation：

    School of Mechanical & Automotive Engineering, Qingdao University of Technology, Qingdao 266520 , China

    ×
  • ， ZHAO Xinsheng

    Affiliation：

    School of Mechanical & Automotive Engineering, Qingdao University of Technology, Qingdao 266520 , China

    ×
  • ， LI Xinming

    Affiliation：

    School of Mechanical & Automotive Engineering, Qingdao University of Technology, Qingdao 266520 , China

    ×

School of Mechanical & Automotive Engineering, Qingdao University of Technology, Qingdao 266520 , China；

通讯作者:

齐博浩(1994—),男(汉),硕士研究生;研究方向:表面改性技术;E-mail:825242782@qq.com

中图分类号:TG178

文献标识码:A

文章编号:1007-9289(2020)05-0010-08

DOI:10.11933/j.issn.1007-9289.20200821001

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目录contents

    摘要

    采用简单的化学刻蚀法在 304 不锈钢网上构造微纳米粗糙结构,随后通过自组装技术将不同链长的脂肪酸装饰到粗糙表面,可制备出具有可控润湿性的网膜;利用接触角测量仪对表面润湿性进行测量,利用原子力显微镜、扫描电子显微镜和傅里叶变换红外光谱仪对网膜表面的形貌和成分进行表征分析,根据长链脂肪酸改性后的超疏水超亲油特性测试油水分离性能以及重复利用性。 结果表明:不锈钢滤网表面呈现二维微纳米粗糙结构,并形成有序碳链薄膜。 通过调节脂肪酸的链长可实现亲水到超疏水的转变,接触角范围为 45° ~ 153°;油滴迅速在网膜上渗透,接触角始终为 0°。 链长越长的脂肪酸疏水亲油效果越明显,油水分离效率越高,最高达到 96%;经重复油水分离 50 次测试后,其油水分离效率仍能达到 80%以上。

    Abstract

    A simple chemical etching method was used to construct a micro-nano rough structure on a 304 stainless steel mesh, and then a self-assembly technique was used to decorate fatty acids with different chain length on the rough surface to control wettability. Atomic force microscope, scanning electron microscope, Fourier transform infrared spectrometer, and contact angle measuring instrument were used to characterize and analyze the morphology, composition, and wettability of the surface. Also the super-hydrophobic and super-oleophilic properties of modified long-chain fatty acids were tested for oil-water separation performance and reusability. The results show that the surface has two-dimensional micro-nano rough structure with ordered carbon chain, and the change from hydrophilic to super-hydrophobic is achieved by adjusting the chain length of the fatty acids, with a contact angle ranging from 45° to 153°. The oil drops quickly penetrate the mesh surface, and the oil contact angle is always 0°. The longer the chain length of the fatty acids, the more the hydrophobic and oleophilic effect of the mesh surface, and the higher the oil-water separation efficiency (up to 96%). After 50 repeated oil-water separation tests, the oil-water separation efficiency is more than 80%.

  • 0 引言

  • 智能响应润湿性材料已在材料学和界面学得到了极大的关注,通过外界刺激(如温度、力、光、电等)来控制表面润湿性,可实现润湿性智能的转变。固体表面的特殊润湿性包括超疏水、超亲水、超疏油、超亲油,将4 个润湿特性进行多元组合和相互转变,可实现材料的单一功能到智能多重转化功能。近年来,材料制备技术得到了不断提高,调控手段更加精细化,因此许多新型智能响应材料[1] 被提出,包括热响应材料[2]、光响应材料[3]、磁响应性材料[4]、可控润湿性材料[5]、 pH响应型材料[6]等。其中可控润湿性材料是通过操控表面结构与表面化学成分来实现润湿性的控制,其种类众多,主要以超疏/亲水可逆转变的润湿性表面为主。 Nakajima等[7]通过改变表面粗糙度来实现润湿性的控制,利用相分离法在四乙基正硅烷中添加丙烯酸聚合物得到坑状结构的粗糙表面,再利用氟硅烷改性修饰得到超疏水薄膜,通过控制丙烯酸聚合物的浓度来改变表面粗糙度,进而实现润湿性的控制。 Wang等[8]在粗糙表面上通过控制化学组成来实现润湿性的控制, 利用电化学沉积法在铜网上制备二元微纳米结构,在粗糙结构上分别修饰不同链长的脂肪酸,表面润湿性随着链长的改变而变化。 Yu等[9] 利用电沉积法制备粗糙的金基底表面,将其直立放于试管中,缓慢滴加十二烷基硫醇,让基体的不同位置对应于不同的改性时间,再经羟基十一醇溶液修饰,基体表面不同位置会表现出不同的润湿性, 从而实现表面从超疏水到超亲水的梯度变化。

  • 智能响应润湿性材料在传感器[10]、生物医学[11]、电催化[12]、流体运动学[13]、油水分离[14] 等领域具有重要意义和应用价值[15-16]。生活环境中油污污染问题已引起人们的重点关注,如何有效实现油水分离成为了待解决的关键问题[17-19]。为此,提出了可控润湿性材料与油水分离相结合的方法,以304 不锈钢网为基底,其优点为具有稳定的物理化学性能,防锈耐腐蚀性能良好,在化学实验中可抵御酸碱溶剂的腐蚀,且网孔大小可自主控制,应用广泛且成本较低。采用化学刻蚀法在304 不锈钢网上构造微纳米粗糙结构,再通过自组装技术将不同链长的脂肪酸修饰到粗糙表面,制备出具有可控润湿性的不锈钢网。当滤网为双亲表面时,可过滤油水混合物中的固体颗粒,当滤网为超疏水超亲油表面时, 可过滤掉油水混合物中的油,以实现对油水混合物的分离。该可控润湿性滤网为解决油水污染问题提供了一种新的可行性方法。

  • 1 试验

  • 1.1 试验材料

  • 试验样品为304 不锈钢网(河北英凯膜公司),74.17 μm(200 目),丝径为0.55 mm,孔径为77 μm, 为保证不锈钢的耐腐蚀性, 需满足w(Cr)≥18%、w(Ni)≥8%,密度为7.93 g/cm 3; 无水乙醇、石油醚(天津市富宇精细化工有限公司);盐酸(都艾科试剂);煤油、正庚烷、三氯甲烷、1,2 二氯乙烷( 聊城胜世化工产品有限公司);95 号汽油(中国石化有限公司);氯化铁、脂肪酸系列CH3(CH2)nCOOH( n=1,2,…,16)(上海阿拉丁科技股份有限公司)包括丙酸、正丁酸、正戊酸、正己酸、庚酸、正辛酸、正壬酸、正癸酸、月桂酸、肉豆蔻酸、软脂酸、硬脂酸。

  • 1.2 试验方法

  • 将304 不锈钢网剪成3 cm×3 cm的正方形, 用石油醚、乙醇、去离子水各超声清洗10 min,氮气吹干,然后将不锈钢网置于盐酸(1 mol/L) 溶液中去除表面氧化膜,再用去离子水清洗并吹干;将预处理的不锈钢网放入已配置好的FeCl3 溶液中刻蚀,随后取出清洗并氮气吹干;最后将刻蚀后的不锈钢网放置到1 mol/L的脂肪酸乙醇溶液中,在40℃ 条件下密封2 h,随后用大量乙醇冲洗除去残留的酸,并氮气吹干,进行表征。

  • 1.3 表征与分析

  • 利用扫描电子显微镜(SEM,S-3500 N,Hitachi日本) 和原子力显微镜( AFM,DI Innova德国)对试样表面形貌进行分析;利用X射线衍射仪(XRD,D8 ADVANCE,Bruker德国) 对试样进行物相分析;利用傅里叶变换红外光谱仪( FTIR,U-4100Hitachi德国) 分析试样表面成分;采用接触角测量仪( JC2000C1B,中晨,上海) 测量液滴在试样表面上的接触角(CA)、滚动角( SA) 以及黏附性。

  • 关于油水分离效率的表征,是基于分离前后油的体积比 K。假设油水混合溶液中水的体积为 V,油的体积是 V1,将油和水混合到一起并进行搅拌,静置一段时间后,使用不锈钢滤网进行油水分离,分离出油的体积是 V2, 则分离效率可定义为:

  • K=V2V1×100%
    (1)

  • 2 试验结果与讨论

  • 2.1 润湿性能分析

  • 润湿性是由表面结构及表面化学组成共同决定的,因此对润湿性的控制可通过操纵表面形貌结构和表面化学组成来实现。文中是在粗糙表面上通过操纵表面的化学组成来控制网膜的润湿性。试验利用刻蚀法在不锈钢网上制备出微纳米二元粗糙结构,然后用不同链长的脂肪酸CH3(CH2)nCOOH( n=1,2,…,16) 在粗糙表面自组装单分子膜。表面粗糙度对润湿性具有放大效应,表面粗糙度增大时,亲液表面的接触角减小,疏液表面的接触角增大,即当粗糙表面为亲水时,液体会浸满粗糙表面的凹槽,此时可用Wenzel方程解释[20],当粗糙表面为强疏水性时, 液体便悬在粗糙表面的凸槽上,此时可用Cassie方程解释[21]。脂肪酸对表面自组装单分子膜时,其结构主要由链长决定,链长对润湿性具有重要影响[22]。当短链酸对粗糙表面修饰时,无序分散的碳链和高能量的不锈钢网导致表面能升高,从而接触角减小;随着分子链长的增加, 填充密度增大,排列更加有序,低能量的基团(—CH3、—CH2)增加,在表面封闭堆积,而高能量的不锈钢表面比例减小,从而表面能降低,接触角随之增大。

  • 经过刻蚀后的不锈钢网,在空气中与氧气形成一层极薄致密的铁的氧化膜和含氧基团(如羟基等)极性物质,这些极性物质与脂肪酸的极性部分羧基产生良好的结合,使其牢固地结合到不锈钢网表面,并使脂肪酸的非极性部分朝外,因此表面形成了一层自组装单分子膜[23-24]。分子膜含有表面能低的—CH3(表面张力为24 mN/m) 和-CH2(表面张力为31 mN/m)基团,可有效控制表面自由能的大小。图1 所示为脂肪酸链长与水、油在相应网膜上的接触角的关系,其中丙酸链长最短,滤网经其改性后,表面呈亲水性,接触角为45°;当正癸酸改性后,表面达到超疏水状态,接触角为150°,随着链长继续增加,接触角有限地增大,最终达到153°。由此,表面的可控润湿性的范围为45°~153°。原始光滑表面的不锈钢网经过不同链长的脂肪酸改性后接触角范围在86°~124°,而用油进行润湿性表征时,其接触角始终为0°。图2 为水滴在经正癸酸与丙酸改性后的薄膜上的接触情况示意图。

  • 图1 脂肪酸链长与水、油在相应网膜上的接触角的关系

  • Fig.1 Relationship between chain length of fatty acids and contact angle for water and oil on the corresponding modified mesh films

  • 图2 正癸酸和丙酸改性后薄膜上水滴的形状

  • Fig.2 Shapes of water droplets on the modified as-prepared films with n-decanoic acid and propionic acid

  • 在润湿性表征中,选用疏水效果最好的正十二烷酸改性的网膜,水滴在该表面上很不稳定, 黏附力极小,很容易滚落,滚动角约为2°,如图3 所示。在粗糙表面和网孔的共同作用下,此时的液滴在不锈钢网表面的实际接触状况是气-液、固-液复合接触状态,该状态是一种Cassie-Baxter模型[25],其方程为cosθr=f 1 cosθ1-f 2,θr 为液体与基体表面的表观接触角,θ1 为液体与基体表面的本征接触角,f 1、f 2 分别为复合接触面积中固-液、气-液所占的比例,其中 f 1 +f 2=1。以水和网膜为例,将 θr=153°,θ1=98°代入Cassie-Baxter方程得,f 1=0.126,f 2=0.874。所以固-液的接触面积占比为12.6%,气-液的接触面积为87.4%。正是这种复合接触状态使网膜具有特殊润湿性。

  • 图3 不锈钢网膜特殊润湿性的表征

  • Fig.3 Characterization of the special wettability of stainless steel films

  • 2.2 表面形貌与成分

  • 图4( a)是原始未处理的不锈钢网SEM形貌,可以看出,表面十分光滑平整,当SEM放大50 000 倍如图4( b)所示,表面才出现极小的纳米级颗粒,所以表面粗糙度十分小。图4( c)(d)是经过刻蚀和自组装单分子膜后的不锈钢网SEM形貌,其表面是一层微纳米级的三维粗糙结构,其中的微团簇附着在每根网丝表面,表面粗糙度明显增大。造成此现象的原因如下:不锈钢网在制作过程中由于拉拔工艺,内部存有大量晶体缺陷,缺陷处点阵畸变较大,原子间的键合力小,因此处于能量较高的状态,当将不锈钢网放入弱酸性氯化铁溶液中,溶液中H +和Fe3+优先从这些能量较高的缺陷处开始反应,即不锈钢网表面的铁与氯化铁溶液开始反应,其反应方程为Fe+2Fe3+→3Fe2+和Fe+2H +→Fe2+ +H2↑,该氧化还原反应正是不锈钢网表面产生微-纳米结构的原因。

  • 图5 为原始不锈钢网与FeCl3 刻蚀的不锈钢网的AFM形貌(扫描范围5 μm×5 μm)。由图5(a) 可以看出,原始不锈钢网表面平整规则,纳米级凸起最高只有16.7 nm,经Nano Scope Analysis软件分析测得原始不锈钢网表面的平均表面粗糙度值 Ra 约为5.55 nm。由图5(b)可以看出,经FeCl3 刻蚀后的表面出现了大量不规则凸峰, 这些凸峰大小不一、形状各异,最高凸起可达71.2 nm,经软件分析测得刻蚀表面的平均表面粗糙度值 Ra 约为23.7 nm,约是原始表面 Ra 的5 倍,所以经刻蚀后表面变得十分粗糙。

  • 图4 原始不锈钢网与超疏水不锈钢网的SEM形貌

  • Fig.4 SEM images of original stainless steel mesh and superhydrophobic stainless steel mesh

  • 图5 原始不锈钢网和超疏水不锈钢网的AFM图像

  • Fig.5 AFM images of original stainless steel mesh and super hydrophobic stainless steel mesh

  • 通过扫描电子显微镜和原子力显微镜的表征分析发现,经刻蚀后的不锈钢网表面粗糙度明显增大,为确定刻蚀反应对表面晶体结构的影响,采用X射线衍射仪对试样进行分析,结果如图6 所示,XRD图谱中A、B分别对应原始不锈钢网、FeCl3 刻蚀的不锈钢网,这2 条曲线均有3 个明显的特征峰, 分别为2θ=43.54°、 2θ=50.64°、2θ=74.62°,分别对应( 111)、( 200)、(220)的晶面衍射峰,与304 不锈钢标准衍射卡( JCPDS:033-0397) 完全相符。该结果说明经FeCl3 刻蚀的不锈钢网与原始不锈钢网的晶体结构并未发生变化,峰值大小表明表面物质的含量略有变化。

  • 图6 不锈钢网的XRD图谱(A:原始不锈钢网,B:FeCl3 刻蚀的不锈钢网)

  • Fig.6 XRD spectra of stainless steel mesh( A: original stainless steel mesh, B: FeCl3 etched stainless steel mesh)

  • 为验证脂肪酸分子膜在不锈钢网表面存在及薄膜的成键特性,采用傅里叶变换红外光谱仪对试样进行分析,结果如图7 所示,红外光谱中高频区图7(a)和低频区图7(b)均存在明显吸收峰。烷基链的波数范围为2840~3000 cm-1,是由C-H伸缩振动引起的。已有研究结果表明,脂肪酸可在金属表面形成有序薄膜,烷基链为全反式结构,并且以偏离表面法线的方向倾斜,从而产生波数小于2918 cm-1 的特征峰[26-28]。在高频区中,3382 cm-1 处的吸收峰对应脂肪酸分子的O-H的伸缩振动,表明分子间和分子内形成了氢键,2904 cm-1 和2850 cm-1 处的吸收峰对应于脂肪酸分子中的-CH3 和-CH2,表明脂肪酸在不锈钢表面形成了有序碳链薄膜。在低频区出现与羧基相关的3 种振动模式[29], 在1427 cm-1 和1531 cm-1 处分别对应由脂肪酸中羧基与金属表面羟基反应生成的酯键中碳氧对称振动和非对称振动, 以及1735 cm-1 处为-COOH部分的C=O的伸缩振动。这些峰的存在和1703 cm-1 处C=O振动的缺失表明脂肪酸羧基头部发生部分离解以及表面形成了新结构-羧酸盐[30]。

  • 图7 改性后不锈钢网的FT-IR图谱

  • Fig.7 FT-IR spectra of modified stainless steel mesh

  • 2.3 油水分离性能

  • 脂肪酸链长越长疏水亲油效果越明显,因此进行油水分离试验时选用效果最好的正十八烷酸,常见油品的表面张力在20~40 mN/m之间, 为评价所制备的不锈钢网的油水分离性能,选用汽油、煤油、正辛烷、三氯甲烷、1,2 二氯乙烷,如表1 所示。采用简单的过滤分离法对油水混合物进行分离试验,分离过程如图8 所示,为便于观察,用红色染色剂和蓝色染色剂分别对油和水染色,并将油水体积比为1 ∶3的油水混合物充分搅拌,然后把混合物缓慢倒在滤网上,由于滤网的超疏水超亲油特性和重力作用,使得水会被排开流出,而油会从滤网上浸透过去并滴落在烧杯中。收集分离后的油水并分析其分离效率,结果如图9 所示,可以看出,不锈钢网对各类油的分离效率均在90%以上,这表明超疏水超亲油特性使不锈钢滤网在油水分离应用中表现出优异的分离性能。

  • 表1 不同液体的表面张力及密度

  • Table1 Surface tension and density of different liquids

  • 图8 油水分离试验

  • Fig.8 Oil-water separation experiment

  • 2.4 重复利用性

  • 采用循环油水分离后不锈钢网的分离效率、接触角及表面形貌来评价超疏水超亲油不锈钢网的重复使用性能,测试方法为:将油水混合物倒在滤网上进行分离,收集油和水,混合后再进行过滤分离,不断重复循环上述分离过程。最后将不锈钢网用氮气吹干,分析不锈钢网的表面形貌和循环不同次数下的分离效率和与水的接触角。结果如图10(a)所示,此时选用煤油与水混合物进行试验,循环不同次数后的分离效率有所降低,但分离效率仍在80%以上,表明不锈钢网具有较好的重复利用性,同时与水的接触角也有所减小。图10(b)为油水分离循环50 次后的表面形貌,可以看出,表面粗糙结构被破坏,粗糙度有所降低。导致油水分离效率降低的原因为:油品在循环使用过程中挥发,导致油的体积减小;滤网在循环过滤和氮气吹干过程中,表面微纳米结构遭到破坏,粗糙度降低;多次循环后油品会黏附在容器和滤网表面,从而导致油的含量减少。

  • 图9 不同油水混合物的分离效率

  • Fig.9 Separation efficiency of different oil-water mixtures

  • 图10 超疏水超亲油不锈钢网经过循环油水分离过程后的分离效率和接触角及循环50 次后滤网表面的形貌

  • Fig.10 Separation efficiency and contact angle of the super-hydrophobic and super-lipophilic stainless steel mesh after circulating oil-water separation process and the morphology of the filter surface after 50 cycles

  • 3 结论

  • (1) 用简单的化学刻蚀法在不锈钢网表面构造微纳米二元粗糙结构,并在粗糙结构上修饰不同链长的脂肪酸分子膜,成功制备了具有亲水到超疏水转变的可控润湿性网膜;当表面分子膜为长链脂肪酸时,表现出对水的高接触角、低滚动角及很低的黏附性,并对油的接触角始终为0°,呈超亲油特性。

  • (2) 经表面形貌分析,刻蚀的表面结构呈二维粗糙结构, 平均表面粗糙度值由原始的5.55 nm增大到23.7 nm,粗糙程度明显提高,对表面润湿性起到放大作用;经傅里叶变换红外光谱仪分析,脂肪酸成功与不锈钢网表面相结合,是自组装单分子膜的关键前提。

  • (3) 基于可控润湿性滤网具有良好油水分离性能,设计油水分离试验,试验中不同油水混合物的分离效率均可达到90%以上,50 次油水分离循环后分离效率仍能达到80%以上,具有良好重复利用性;可控润湿性滤网与油水分离问题完美结合,对于解决环境中的油水污染问题具有一定的意义和实用价值。

  • 参考文献

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    • [9] YU X,WANG Z,ZHANG X,et al.Surface gradient materi-al:from superhydrophobicity to superhydrophilicity [J].Langmuir,2006,22(10):4483-4486.

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    • [16] SHANNON M A,BOHN P W,ELIMELECH M,et al.Sci-ence and technology for water purification in the coming dec-ades[J].Nature,2008,452(7185):301-310.

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    • [21] YAN Y Y,GAO N,BARTHLOTT W.Mimicking natural su-perhydrophobic surfaces and grasping the wetting process:a review on recent progress in preparing superhydrophobic sur-faces[J].Advance in Colloid and Interface Science,2011,169(2):80-105.

    • [22] SHUSTAK G,DOMB A J,MANDLER D,et al.Preparation and characterization of n-alkanoic acid self-assembled mono-layers adsorbed on 316L stainless steel [J].Langmuir,2004,20(18):7499-7506.

    • [23] GUSTAFSSON L,JANSSON R,HEDHAMMAR M,et al.Structuring of functional spider silk wires,coatings,and sheets by self-assembly on superhydrophobic pillar surfaces [J].Advanced Materials,2018,30(3):1704325.

    • [24] GAO A,WU Q,WANG D,et al.A superhydrophobic sur-face templated by protein self-assembly and emerging applica-tion toward protein crystallization[J].Advanced Materials,2016,28(3):579-587.

    • [25] CASSIE A B D,BAXTER S.Wettability of porous surfaces[J].Transactions of the Faraday Society,1944,40:546-551.

    • [26] TAO Y T.Structural comparison of self-assembled monolay-ers of n-alkanoic acids on the surfaces of silver,copper,and aluminum[J].Journal of the American Chemical Society,1993,115(10):4350-4358.

    • [27] RAMAN A,GAWALT E S.Self-assembled monolayers of al-kanoic acids on the native oxide surface of SS316L by solu-tion deposition[J].Langmuir,2007,23(5):2284-2288.

    • [28] RAMAN A,QUINONES R,BARRIGER L,et al.Under-standing organic film behavior on alloy and metal oxides[J].Langmuir,2010,b 26(3):1747-1754.

    • [29] NAKAMOTO K,FUJITA J,TANAKA S,et al.Infrared spectra of metallic complexes.IV.comparison of the infrared spectra of unidentate and bidentate metallic complexes[J].Journal of the American Chemical Society,1957,79(18):4904-4908.

    • [30] SHUSTAK G,DOMB A J,MANDLER D,et al.Preparation and characterization of n-alkanoic acid self-assembled mono-layers adsorbed on 316L stainless steel [J].Langmuir,2004,20(18):7499-7506.

  • 基本信息

    中图分类号: TG178
    文献标识码: A
    DOI: 10.11933/j.issn.1007-9289.20200821001
    文章编号: 1007-9289(2020)05-0010-08

    基金信息

    国家自然科学基金(51875299)；
    Supported by National Natural Science Foundation of China (51875299)；

    引用信息

    李志文, 齐博浩, 刘长松, 等. 不锈钢网表面润湿性的调控及其油水分离性能[J]. 中国表面工程, 2020, 33(5): 10-17.

    LI Z W, QI B H, LIU C S, et al. Manipulation of surface wettability on stainless steel mesh and its oil-water separation performance [J]. China Surface Engineering, 2020, 33(5): 10-17.

    稿件历史

    收稿日期: 2020-08-21

  • 参考文献

    • [1] NGUYEN V Q,AHMED A S,RAMANUJAN R V.Mor-phing soft magnetic composites [J].Advanced Materials,2012,24(30):4041-4054.

    • [2] KANAZAWA H.Thermally responsive chromatographic ma-terials using functional polymers[J].Journal of Separation Science,2015,30(11):1646-1656.

    • [3] ZOU X,ZHANG Y.Noble metal-free hydrogen evolution catalysts for water splitting[J].Chemical Society Reviews,2015,44:5148-5180.

    • [4] SONG T,CAI X,TU M W,et al.Giant tunneling magneto-resistance in spin-filter van der waals heterostructures [J].Science,2018,360:1214-1218.

    • [5] WANG J N,LIU Y Q,ZHANG Y L,et al.Wearable super-hydrophobic elastomer skin with switchable wettability [J].Advanced Functional Materials,2018:1800625.

    • [6] LI X,ZHANG Q,ZHANG W,et al.Smart nylon mem-branes with pH-responsive wettability:high-efficiency separa-tion on demand for various oil/water mixtures and surfactant-stabilized emulsions [J].Advanced Materials Interfaces,2018,5:1181179.

    • [7] NAKAJIMA A,ABE K,HASHIMOTO K,et al.Preparation of hard super-hydrophobic films with visible light transmission [J].Thin Solid Films,2000,376:140-143.

    • [8] WANG S T,FENG L,LIU T L,et al.Manipulation of sur-face wettability between superhydrophobicity and superhydro-philicity on copper films [J].ChemPhysChem,2005,6(8):1475-1478.

    • [9] YU X,WANG Z,ZHANG X,et al.Surface gradient materi-al:from superhydrophobicity to superhydrophilicity [J].Langmuir,2006,22(10):4483-4486.

    • [10] FENG X J,JIANG L.Design and creation of superwetting/antiwetting surfaces [J].Advanced Materials,2010,18(23):3063-3078.

    • [11] CHU Z,FENG Y,SEEGER S,et al.Oil/Water separation with selective superantiwetting/superwetting surface saterials [J].Angewandte Chemie International Edition,2015,54(8):2328-2338.

    • [12] LIAO Q,WANG H,ZHU X,et al.Liquid droplet movement on horizontal surface with gradient surface energy[J].Sci-ence in China,Series E,2006,49(6):733-741.

    • [13] WANG K X,LI X H,CHEN J S,et al.Surface and inter-face engineering of electrode materials for lithium-ion batter-ies[J].Advanced Materials,2015,27:527-545.

    • [14] LI X,ZHANG K J,MITLIN D,et al.Fundamental insight into Zr modification of Li-and Mn-rich cathodes:combined transmission electron microscopy and electrochemical imped-ance spectroscopy study[J].Chemistry of Materials,2018,30:2566-2573.

    • [15] GAO A,HANG R,LI W,et al.Linker-free covalent immo-bilization of heparin,SDF-1a,and CD47 on PTFE surface for antithrombogenicity,endothelialization and antiinflamma-tion[J].Biomaterials,2017,140:201-211.

    • [16] SHANNON M A,BOHN P W,ELIMELECH M,et al.Sci-ence and technology for water purification in the coming dec-ades[J].Nature,2008,452(7185):301-310.

    • [17] CORTESE B,CASCHERA D,FEDERICI F,et al.Super-hydrophobic fabrics for oil-water separation through a dia-mond like carbon(DLC)coating[J].Journal of Materials Chemistry A,2014,2(19):6781-6789.

    • [18] AL-MAJED A A,ADEBAYO A R,HOSSAIN M E.A sus-tainable approach to controlling oil spills[J].Journal of En-vironmental Management,2012,113(1):213-227.

    • [19] HASSLER B.Accidental versus operational oil spills from shipping in the baltic sea:risk governance and management strategies[J].Ambio,2011,40(2):170-178.

    • [20] WENZEL,ROBERT N.Resistance of solid surfaces to wet-ting by water [J].Transactions of the Faraday Society,1936,28(8):988-994.

    • [21] YAN Y Y,GAO N,BARTHLOTT W.Mimicking natural su-perhydrophobic surfaces and grasping the wetting process:a review on recent progress in preparing superhydrophobic sur-faces[J].Advance in Colloid and Interface Science,2011,169(2):80-105.

    • [22] SHUSTAK G,DOMB A J,MANDLER D,et al.Preparation and characterization of n-alkanoic acid self-assembled mono-layers adsorbed on 316L stainless steel [J].Langmuir,2004,20(18):7499-7506.

    • [23] GUSTAFSSON L,JANSSON R,HEDHAMMAR M,et al.Structuring of functional spider silk wires,coatings,and sheets by self-assembly on superhydrophobic pillar surfaces [J].Advanced Materials,2018,30(3):1704325.

    • [24] GAO A,WU Q,WANG D,et al.A superhydrophobic sur-face templated by protein self-assembly and emerging applica-tion toward protein crystallization[J].Advanced Materials,2016,28(3):579-587.

    • [25] CASSIE A B D,BAXTER S.Wettability of porous surfaces[J].Transactions of the Faraday Society,1944,40:546-551.

    • [26] TAO Y T.Structural comparison of self-assembled monolay-ers of n-alkanoic acids on the surfaces of silver,copper,and aluminum[J].Journal of the American Chemical Society,1993,115(10):4350-4358.

    • [27] RAMAN A,GAWALT E S.Self-assembled monolayers of al-kanoic acids on the native oxide surface of SS316L by solu-tion deposition[J].Langmuir,2007,23(5):2284-2288.

    • [28] RAMAN A,QUINONES R,BARRIGER L,et al.Under-standing organic film behavior on alloy and metal oxides[J].Langmuir,2010,b 26(3):1747-1754.

    • [29] NAKAMOTO K,FUJITA J,TANAKA S,et al.Infrared spectra of metallic complexes.IV.comparison of the infrared spectra of unidentate and bidentate metallic complexes[J].Journal of the American Chemical Society,1957,79(18):4904-4908.

    • [30] SHUSTAK G,DOMB A J,MANDLER D,et al.Preparation and characterization of n-alkanoic acid self-assembled mono-layers adsorbed on 316L stainless steel [J].Langmuir,2004,20(18):7499-7506.

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