以无机金属材料为基体的疏水表面制备

发布时间：2018-03-26 17:43

  本文选题：无机基体　切入点：铝片　出处：《湖南大学》2016年硕士论文

【摘要】：超疏水表面的应用价值是不可限量的,但是目前制备高机械性能、耐腐蚀性表面还存在很大的难度。本论文参考了大量的文献工作,以无机金属材料为基体,进行了表面疏水材料的制备。主要开展了电沉积法制备硬脂酸表面、电沉积法制备氧化铈疏水表面、水热法制备片状Co3O4/Al疏水表面和水热法制备C0304/泡沫镍疏水表面等工作的研究,通过改变实验条件,考察了表面形貌对疏水性、机械性能和腐蚀性的影响。主要结论如下：(1)采用电沉积方法在铝板表面构筑了Ce02-硬脂酸/Al疏水表面。FT-IR分析结果表明经过电沉积处理,在铝板表面成功沉积得到了硬脂酸涂层；SEM分析表明沉积表面主要存在着两种形貌：定向生长的乳状凸起和“中间凹,周边凸”的片状结构；EDS分析表明沉积表面不同形貌对应元素含量存在较大的差异,说明在沉积过程中,电解质中的不同组分存在选择性的生长；建立了四因素、三水平(L934)的正交试验,考察了电沉积过程中硝酸铈浓度、硬脂酸浓度、电沉积电压以及电沉积时间等因素,并对实验结果进行了SEM测试和WCA测试,研究了电沉积表面的形貌与接触角之间的关系。SEM测试结果表明电沉积过程中铝板表面会形成了不同的形貌,主要以针状结构和乳状凸起为主。根据不同样品的原料配比可知,硝酸铈浓度越高,越有利于形成针状结构；硬脂酸浓度越高,表面越有利于形成乳状凸起结构；当这两种原料的浓度均较高时,表面趋向平整,并伴随有一些裂纹存在；通过正交试验研究了各实验因素对实验结果的影响,由极差分析可知,各影响因素对接触角的影响如下：硝酸铈浓度电沉积电压电沉积时间硬脂酸浓度。最佳制备条件为：0.02 mol/L硝酸铈,0.15 mol/L硬脂酸,沉积电压10 V,沉积时间40 min。在最佳制备条件下,接触角可达131°。(2)通过电沉积方法制备了氧化铈/Ni疏水表面,对疏水表面的组成、形貌以及机械性能进行了考察。XRD测试表明电沉积后载体表面有氧化铈的沉积；通过SEM发现沉积后表面存在着很多的缺陷,在超声处理5 min后表面负载物大量脱落,这也说明材料的机械性能有待进一步的提升；采用三种不同的载体进行了氧化铈的电沉积,简单考察了载体对表面疏水性的影响。其中,泡沫镍的疏水性最好(接近140°),金属Ni-A1合金网的疏水性其次(约为120°),压平泡沫镍的疏水性最差(仅为115°)。这些结果说明了网络结构载体对疏水性的构筑是有利的,这与Cassie模型是吻合的。同时,这些结果也表明单纯无机物改性可以获得疏水表面,但仍未达到超疏水的水平。采用了硅胶浸渍法和磷酸锌浸渍法来提升负载物与载体间的结合力,对处理后的机械性能进行了考察。实验结果表明,硅胶浸渍处理不仪可以提高负载物与载体间的结合力,还不影响载体的疏水性；而硫酸锌处理虽然也可以提升负载物与载体间的结合力,但是会极大的影响载体的疏水性,其中压平泡沫镍经过处理后转变为超亲水,这也说明硅胶浸渍处理为更好的载体处理方式。(3)采用水热法合成了Co3O4/Al复合物,并对该复合物的组分、形貌进行了XRD和SEM表征。XRD测试表明经过水热处理,铝板表面生成了α-Co(OH)2,且经过在500℃空气中煅烧3 h后,铝板表面的α-Co(OH)2转化成为了Co3O4; SEM测试表明较低的CTAB、较长的合成时间或较高的合成温度均不利于合成规整形貌的片状结构；而当这些因素处于比较合适的范围时,才能合成规整形貌的片状结构；当合成时间过长且原料浓度较高时,材料表面的大颗粒会大量堆积,导致材料表面的形貌十分粗糙,呈现不规整性；因此,各因素的合理调控对于表面形貌具有很大的影响；设计了四因素、三水平(L934)的正交试验,考察了硝酸钴浓度、CTAB浓度、合成时间和合成温度对材料表面形貌的影响。对制备得到的CoO4/Al复合物进行PFAS疏水改性,并进行了接触角测试,探讨了表面形貌与材料疏水性之间的关系；通过极差分析,各因素对疏水性的影响程度如下：合成温度CTAB浓度硝酸钻浓度合成时间；最佳制备条件为：硝酸钴质量为1.2 g,CTAB质量为0.15 g,水热合成时间为18 h,水热合成温度为100℃；最佳条件下接触角为158°。对PFAS疏水改性后的载体进行了机械性能测试。通过机械性能的测试发现,C0304与铝板间的结合力较差,这可能是因为铝板表面过于光滑,粗糙度不够,不能为C0304提供牢固的生长位点而引起的。(4)采用水热法合成了C0304/泡沫镍复合物,并对该复合物的形貌、组分进行了XRD和FT-IR表征。XRD谱图表明烧制后α-Co(OH)2转变为了Co3O4, FT-IR谱图进一步证实了这个结论;设计了单因素试验,考察了水热合成时间和水热合成温度对材料表面形貌的影响。在合成时间的考察中,随着合成时间的增长,材料的接触角逐渐增大,说明合成时间对接触角有着很大的影响。从形貌上说,合成时间的延长有利于在平泡沫镍表面形成良好的规整形貌。随着合成时间进一步的延长,泡沫镍表面生长的C0304生长为半花状结构,表面规整度提高,接触角也明显增大,变为144°。当时间增大到18h后,接触角得到了进一步的提升,变为156°,处于超疏水的范围；继续延长时间,花状结构变为片状结构,接触角虽然略有下降,但仍处于超疏水；合成温度对接触角的影响也比较大。适宜的温度范围内,接触角处于超疏水的范围,温度过高或偏低,接触角都会明显降低。对PFAS疏水改性后的载体进行了耐腐蚀性能测试,测试了耐腐蚀性能。空白泡沫镍在经过浸渍处理后,表面形貌破坏十分严重。接触角也由最初的76°下降为33°、67°、58°。说明未经负载和改性的泡沫镍,耐腐蚀性能较差；与空白泡沫镍相比,PFAS改性处理后,泡沫镍的疏水性有了明显的提升,但相比于未腐蚀前的102°,仍有了很大程度的下降,均转变为亲水状态。说明单一PFAS改性对泡沫镍耐腐蚀性是不够的。负载不同形貌C0304的泡沫镍在PFAS改性后具有很好的抗腐蚀能力,在经过酸碱盐处理后仍然可以维持良好的疏水性。而且,可以发现花状和片状结构与不完整花状结构相比,疏水性更为良好,经过耐腐蚀测试后接触角分别为152°和155°。这说明表面负载Co3O4对疏水性起着更为重要的影响。
[Abstract]:The application value of super - hydrophobic surface is not limited , but it is difficult to prepare high mechanical and corrosion - resistant surface at present . This paper makes a study on the preparation of surface hydrophobic material by using inorganic metal material as matrix . The main conclusions are as follows : ( 1 ) The surface morphology has been prepared on the surface of aluminum plate by electrodeposition method . The results of FT - IR analysis show that Ce02 - stearic acid / Al hydrophobic surface has been constructed on the surface of aluminum plate .
The SEM analysis showed that the deposition surface mainly existed two kinds of morphology : the shape - like bulge with directional growth and the lamellar structure of " middle concave and peripheral convex " ;
EDS analysis shows that there is a large difference in the content of the corresponding elements in the deposited surface , and the selective growth of different components in the electrolyte during the deposition process is explained .
A four - factor , three - level ( L934 ) orthogonal test was established to investigate the factors such as concentration of cerium nitrate , concentration of stearic acid , electrodeposition voltage and electrodeposition time during electrodeposition .
The higher the concentration of stearic acid , the more favorable the surface is , the more favorable the structure is formed .
When the concentration of the two kinds of raw materials is higher , the surface tends to be flat and accompanied by some cracks .
The effects of various experimental factors on the experimental results were studied by orthogonal experiments . The influence factors on the contact angle were determined by the polarization analysis . The optimum conditions were : 0.02 mol / L cerium nitrate , 0.15 mol / L stearic acid , 10 V deposition voltage and 40 min deposition time . The composition , morphology and mechanical properties of the hydrophobic surface were investigated by electrodeposition .
It was found that there were a lot of defects on the surface after 5 min of ultrasonic treatment , and the mechanical properties of the materials needed to be further improved .
The electrodeposition of cerium oxide was carried out by three different carriers , and the influence of the carrier on the surface hydrophobicity was investigated . The hydrophobic property of Ni - Al alloy was better than that of Cassie model .
XRD and SEM characterization of 伪 - Co ( OH ) 2 on the surface of aluminum plate have been carried out by hydrothermal method .
When these factors are in the appropriate range , the sheet - like structure with regular topography can be synthesized .
When the synthesis time is too long and the concentration of the raw materials is high , large particles on the surface of the material can be accumulated in a large amount , so that the appearance of the surface of the material is very rough , and the irregularity is presented ;
Therefore , the reasonable regulation of each factor has great influence on the surface topography ;
A four - factor and three - level ( L934 ) orthogonal test was designed to investigate the effects of cobalt concentration , CTAB concentration , synthesis time and synthesis temperature on the surface morphology of the material .
The influence degree of each factor on hydrophobicity is as follows : synthesis temperature ( CTAB ) concentration nitric acid drilling concentration synthesis time ;
The optimum conditions were as follows : the mass of cobalt nitrate was 1.2 g , the mass of CTAB was 0.15 g , the hydrothermal synthesis time was 18 h , and the hydrothermal synthesis temperature was 100 鈩，

本文编号：1668890