| 引用本文: | 陈亚西,王思雍,丁国民.石墨烯基双面神超浸润膜的制备及浸润性能[J].哈尔滨工业大学学报,2022,54(5):74.DOI:10.11918/202107100 |
| CHEN Yaxi,WANG Siyong,DING Guomin.Preparation and wetting properties of graphene-based super-wettable Janus membrane[J].Journal of Harbin Institute of Technology,2022,54(5):74.DOI:10.11918/202107100 |
|
| 摘要: |
| 近年来,一侧亲水、一侧疏水的双面神膜由于具有特殊的性质而倍受关注。双面膜大多由亲水和疏水两种材料复合而成,但存在界面结合强度低且亲疏水转化不可逆等缺点。本文基于石墨烯膜制备出一侧亲水、一侧疏水且亲疏水状态可逆转换的双面神膜。首先,对氧化石墨烯（GO）/二苯醚体系进行高速剪切处理,得到GO/二苯醚“水包油”皮克林乳液,对该乳液进行冷冻干燥,采用碘化氢（HI）化学还原,获得微米尺度碗状薄壁球壳的石墨烯基疏水膜。然后,利用等离子体处理,在石墨烯膜一侧引入COOH、CO和C—O等含氧官能团,将两侧疏水的石墨烯膜转换成一侧疏水、一侧超亲水的浸润膜,采用电焦耳热处理将超亲水表面恢复为疏水表面。最后,通过测量静态接触角检验亲疏水转化的稳定性；借助高速摄像机记录水滴在石墨烯双面膜的动态铺展过程。结果表明:等离子体处理疏水石墨烯膜10 s,可将其变成超亲水状态,在20 V直流电压下石墨烯膜在8 s内可由亲水恢复至疏水；经历10次可重复亲疏水转化后,仍保持亲水状态接触角为0°而疏水状态接触角为152°；水滴在亲水表面仅需20 ms即可完全铺展。利用X射线光电子能谱法(XPS)表征材料表面化学官能团；采用扫描电子显微镜(SEM)和透射电子显微镜(TEM)分析微观结构形貌。材料在等离子体和焦耳热处理过程中保持壳壁连通的碗状微球结构恒定是亲疏水可逆循环转化的关键,纯石墨烯成分是这两种处理手段得以实现的保证。 |
| 关键词: 石墨烯 疏水 超亲水 双面神材料 |
| DOI：10.11918/202107100 |
| 分类号:TB321 |
| 文献标识码:A |
| 基金项目:安徽省教育厅项目(KJ2018B13) |
|
| Preparation and wetting properties of graphene-based super-wettable Janus membrane |
|
CHEN Yaxi1,WANG Siyong2,DING Guomin2
|
|
(1.School of Material Science and Chemical Engineering, Chuzhou University, Chuzhou 239000, Anhui, China; 2.Center for Composite Materials and Structure, Harbin Institute of Technology, Harbin 150001, China)
|
| Abstract: |
| In recent years, Janus membrane, whose one side is hydrophilic and the other is hydrophobic, has attracted much attention due to its special properties. Janus membrane is generally composited by hydrophobic material and hydrophilic material, while it has the defects of low interfacial bonding strength and irreversible conversion. In this study, a graphene-based Janus membrane with different wettability properties on both sides was prepared, whose hydrophobic surface could be reversibly transformed into super-hydrophilic surface. First, the graphene oxide (GO)/diphenyl ether system was treated with high-speed shear to prepare stabilized Pickering emulsion, and the emulsion was lyophilized and reduced with hydrogen iodide (HI) to fabricate graphene-based hydrophobic material with bowl-shaped and thin-walled spherical shell structure. Then, oxygen functional groups, such as COOH, CO and C—O, were attached to one side of the membrane by means of plasma treatment, so the hydrophobic graphene-based membrane was transformed into the super-wettable Janus membrane with different wettability properties on both sides, and the super-hydrophilic surface could be restored to hydrophobic surface by electric Joule heat treatment. Finally, the stability of the hydrophilic-hydrophobic conversion was tested by static contact angle, and the dynamic spreading process of water droplet on the graphene-based Janus membrane was recorded via a high-speed video camera. Results show that it cost 10 s to change the hydrophobic graphene-based membrane into the super-hydrophilic under plasma treatment, and the hydrophilic-hydrophobic conversion was completed in 8 s under DC voltage (20 V). After 10 cycles of hydrophilic-hydrophobic conversion, the hydrophilicity contact angle remained 0° and the hydrophobicity contact angle was 152°. It only took 20 ms for the water droplet to complete the spreading process on the hydrophilic surface of the graphene-based membrane. The chemical functional groups of the material were analyzed by XPS, and the microstructure was characterized by SEM and TEM. The structure of bowl-shaped spherical micro shell connected by the holes in the wall was the key to fulfill the hydrophilic-hydrophobic conversion of the material under plasma treatment and electric Joule heat treatment, and the pure graphene component was the base of the two treatments. |
| Key words: graphene hydrophobic super-hydrophilic Janus material |
