地球上可供人類直接使用的淡水資源僅佔全球總水量的0.26%。鑑於水資源的有限供應，從大氣中捕獲霧氣轉化為可用水資源的方法，在環境友善和永續發展方面具有極大的潛力。研究人員從仙人掌植物（Cactaceae）獨特的針狀葉結構中獲得靈感，開發了模仿這些設計的捕霧裝置。
然而，許多現有方法耗時且涉及多個複雜的步驟。在我們的研究中，我們介紹了一種新穎的方法，用於製造模仿仙人掌針葉結構的多層次結構，具有雙重濕潤性表面，用於增強捕捉和收集霧氣的效率。我們的方法之所以出眾，是因為其簡單、快速、低成本且低耗能。通過利用光固化（SLA）3D列印設備並使用樹脂材料，我們成功地創造了一種新穎的仿生結構。透過實驗分析，我們展示了仿仙人掌結構在捕捉霧氣方面的優越性能。與平坦表面相比，我們的結構收集了顯著更多的霧氣，集水效率達到2.10 g/h，而平坦表面的集水效率僅為0.98 g/h。這些結果突顯了我們方法在利用捕捉霧氣轉化成水資源方面的成效。
通過提供高效的霧氣收集方法，我們的研究有助於解決淡水短缺的迫切問題。隨著進一步的發展和應用，這些方法具有巨大的潛力，能夠減輕缺水危機並促進水資源的永續利用。為了進一步提高霧氣收集的性能，我們設計了一種創新的組件式設計，並結合聚乙二醇單甲基丙烯酸（Poly(ethylene glycol) methacrylate）高分子嫁接表面處理法，以得到雙重濕潤性表面。透過雷射共軛焦顯微鏡和掃描式電子顯微鏡對表面形貌和微觀結構特徵進行表面形貌分析。這種高效率且簡單製備的方法可進一步應用於提高霧氣收集性能，並在製造雙重濕潤性表面和微流體設備上得以應用。

Freshwater resources available for direct human use constituted only 0.26% of the total water on Earth. Given the limited availability, capturing water vapor from the atmosphere held immense potential as an eco-friendly and sustainable solution. Researchers had drawn inspiration from the unique leaf structures of cactus plants (Cactaceae) to develop fog collectors that mimicked these designs. However, many of these existing methods were time-consuming and involved multiple complex steps. In our study, we introduced a novel approach for fabricating cactus-inspired multilevel structures with dual-wettability surfaces, designed specifically to efficiently capture and collect fog.
Our method stood out due to its simplicity, speed, affordability, and low energy consumption. By utilizing Stereolithography Apparatus (SLA) 3D printing technology and resin materials, we successfully created these innovative structures. Through experimental analysis, we demonstrated the superior fog collection capabilities of our cactus-inspired structures. When comparing them with a flat substrate, our structures collected a significantly higher amount of fog, measuring 2.10 grams per hour compared to 0.98 grams per hour for the flat substrate. These results highlighted the effectiveness of our approach in harnessing fog as a valuable water resource. By offering a practical and efficient fog collection method, our research contributed to addressing the pressing issue of freshwater scarcity. With further development and implementation, such approaches held immense potential for alleviating the water crisis and promoting sustainable water management practices.
To enhance fog harvesting performance, we employed an assembly design that incorporated Poly(ethylene glycol) methacrylate (PEGMA) polymer grafting to create a dual-wettability surface. The surface's morphology and microstructural features were analyzed using scanning laser confocal microscopy and Scanning Electron Microscope (SEM). This simple and effective method could be extended for utilization in fog harvesting, wettable surfaces, and microfluidic devices.

Figure Caption--------------------------------------------I
Table Caption---------------------------------------------IX
Chapter 1. Introduction-----------------------------------1
Chapter 2. Literature Review------------------------------5
2.1 Surface Wettability-----------------------------------5
2.1.1 Water Contact Angle---------------------------------5
2.1.2 Classic Wetting Models------------------------------6
2.2 Fog Harvesting Behaviors in Nature--------------------11
2.2.1 Cactus Plant----------------------------------------11
2.2.2 Namib Desert Beetle---------------------------------15
2.3 Bioinspired Surfaces for Fog Collection---------------17
2.4 Fabrication of Hybrid-Wettability Surfaces------------23
2.4.1 Laser Etching Method--------------------------------23
2.4.2 Photolithography Method-----------------------------26
2.4.3 Spray Coating Method--------------------------------27
2.4.4 Polymer Grafting------------------------------------29
2.4.5 Mixing Method---------------------------------------31
2.5 Surface Modification----------------------------------37
2.5.1 Atmospheric Pressure Plasma Treatment---------------37
2.5.2 Polymer Grafting------------------------------------41
Chapter 3. Experimental Methods---------------------------42
3.1 Stereolithography 3D Printing Technique---------------44
3.2 Surface Modification----------------------------------49
3.2.1 Atmosphere Pressure Plasma Techniques---------------49
3.2.2 Preparation of Dual-Wettability Surfaces------------50
3.3 Characterization--------------------------------------54
3.3.1 Surface Topography----------------------------------54
3.3.2 Electron Spectroscopy for Chemical Analysis---------56
3.4 Static Water Contact Angle Measurement----------------58
3.5 Fog Collection Experiment-----------------------------59
Chapter 4. Results and Discussion-------------------------61
4.1 Characterization--------------------------------------61
4.1.1 Contact Angle Measurement---------------------------61
4.1.2 Electron Spectroscopy for Chemical Analysis---------62
4.1.3 SEM Analysis----------------------------------------67
4.2 Cactus-Inspired Conical Structures--------------------68
4.2.1 Surface Topography----------------------------------68
4.2.1 Comparative Analysis of Fog Collection Performance--71
4.3 Dual-Wettability Optimization-------------------------81
4.3.1 Surface Topography----------------------------------81
4.3.2 Fog Collection Performance--------------------------83
4.4 Additional Structures---------------------------------91
4.4.1 Frustum Structure-----------------------------------91
4.4.2 Rounded-Conical Structure---------------------------94
4.4.3 Dendritic Structure---------------------------------97
4.5 Comparison with Recent Studies------------------------100
Chapter 5. Conclusions------------------------------------104
Chapter 6. Future Work------------------------------------109
6.1.1 Design Capacity Patterns for Enhancing Fog Collection--109
6.1.2 Material Selection of Additive Manufacturing-----------110
References------------------------------------------------111

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