微纳分级结构超疏水金属表面的电沉积构筑及性能∗

表面粗糙度和表面自由能是影响材料超疏水特性的两个主要因素。 为了获得同时具有微纳分级结构和低表面能的超疏水金属镀层,在低共熔溶剂中采用先构筑微米尺度结构,再构筑低表面能纳米尺度结构的两步电沉积策略。 利用 SEM、EDS 和 FTIR 观察不同沉积时间(t = 0、0. 5、1 和 2 min)下沉积样品(分别命名为 Zn、Zn / Zn myristate-0. 5、Zn / Zn myristate-1 和 Zn / Zn myristate-2)的表面形貌和成分。 利用接触角测量仪和电化学工作站分析样品的超疏水性、耐腐蚀性、自清洁性及化学稳定性。 结果表明,Zn / Zn myristate 镀层表面呈现由微米尺度的纯锌多面体和纳米尺度的十四酸锌薄片构筑而成的微纳分级结构;随着沉积时间增加,十四酸锌纳米薄片逐渐长大、交联并形成网状结构。 得益于其特殊的表面微纳结构和表面组成,Zn / Zn myristate-2 镀层表现出优异的超疏水(CA = 156. 7±1. 5°、SA = 2. 5±0. 3°)、耐腐蚀和自清洁特性。 稳定性测试表明,Zn / Zn myristate-2 镀层在空气(12 周)和 3. 5 wt. %的 NaCl 溶液(6 d)中表现出优异的超疏水稳定性。

Electrodeposition and Properties of Micro / nanoscale Hierarchical Structured Superhydrophobic Metal Surface

Surface roughness and surface free energy are two of the most important influence factors of superhydrophobicity. To fabricate the superhydrophobic metal surface with micro / nanoscale hierarchical structures and low surface free energy, two-step electrodeposition method was employed to construct microscale and nanoscale structure with low surface free energy. The surface morphologies and composition of coatings with different deposition time (They were named Zn, Zn / Zn myristate-0. 5, Zn / Zn myristate -1 and Zn / Zn myristate-2 on the basis of the deposition time, respectively) were characterized by SEM, EDS and FTIR. The superhydrophobicity, corrosion resistance, self-cleaning effect and chemical stability of metal coatings were evaluated by contact angle measuring instrument and electrochemical workstation. The results show that Zn / Zn myristate surface has micro / nanoscale hierarchical structure, which is composed of microscale polyhedral Zn and nanoscale flake-like Zn myristate. As the deposition time increases, flake-like Zn myristate gradually grows and forms reticulate structures. The Zn / Zn myristate-2 coating shows excellent superhydrophobicity (CA= 156. 7 ± 1. 5°, SA = 2. 5 ± 0. 3°), corrosion resistance and self-clean due to its unique micro / nanoscale structures and low surface free energy. Stability test result shows Zn / Zn myristate-2 coating exhibits excellent chemical stability in air(12 weeks) and 3. 5 wt. % NaCl solusion (6 d).