Bionic technology Lab

1. Bionic technology Lab Superhydrophobic transparent films from silica powder: Comparison offabrication methods 指導教授: 蔡平賜 學生: 尹新輝 KUAS Chemical Engineering

2. KUAS Chemical Engineering 4 Experiment Abstract 1 3 2 Introduction Bionic technology Lab -Outline- Results & Discussion

3. KUAS Chemical Engineering Bionic technology Lab -Abstract- The lotus leaf is known for its self-clean, superhydrophobic surface, which displays a hierarchical structure covered with a thin wax like material. 蓮葉表面因為覆蓋階層式臘質結構，所以能達到自潔及超疏水的功能。 In this study, three fabrication techniques, using silicon dioxide particles to create surface roughness followed by a surface modification with a film of polydimethylsiloxane(PDMS),were applied on a transparent glass substrate. 三種技術都是用silicon dioxide particles創造粗糙表面再coat PDMS薄膜來進行表面改質。

4. KUAS Chemical Engineering Bionic technology Lab -Abstract- The fabrication techniques differed mainly on the deposition of silicon dioxide particles, which included organic, inorganic, and physical methods. 不同的製造技術但其最主要為沉積silicon dioxide particles，其技 術分為有機、無機、物理法。 Each technique was used to coat three samples of varying particle load. 每種技術都是coat三種樣品且不同粒子負載。 The surface of each sample was evaluated with contact angle goniometer and optical spectrometer. 將每個樣品的表面進行接觸角及穿透度的測試。

5. KUAS Chemical Engineering Bionic technology Lab -Abstract- Results confirmed the inverse relationships between contact angle and optical transmissivity independent of fabrication techniques. 個別的實驗結果皆證實接觸角與穿透度為反比關係。 Microstructural morphologies also suggested the advantage of physical deposition over chemical methods. 微結構型態建議物理沉積法。 In summary, the direct sintering method provedoutstanding for its Contact angle vstransmissivity efficiency, and capable of generating a contact angle as high as 174°. 綜合上述結果，直接燒結法能產生良好的接觸角及穿透度，其接觸角可 高達174°。

6. KUAS Chemical Engineering Bionic technology Lab -Introduction-Lotus Effect Micro structure Nano structure Barthlott and Neinhuis, Planta, 1997, 202, 1[1] • Superhydrophobic surfaces High contact angle Low contact angle hysteresis

7. KUAS Chemical Engineering Bionic technology Lab -Introduction- Application • Outdoor solar panels • LED covers

8. KUAS Chemical Engineering Bionic technology Lab -Experiment- 實驗藥品: TEOS(tetraethoxysilane)Sigma - Aldrich PDMS(polydimethylsiloxane)Sigma - Aldrich 3-Aminopropyl triethoxysilane(APS)Sigma – Aldrich 3-Glycidoxypropyltriethoxysilane(GPS) Sigma – Aldrich

9. KUAS Chemical Engineering Bionic technology Lab -Experiment- 量測儀器: FTA125(測接觸角) Ocean Optics USB2000 FibreOptic Spectrometer(測穿透度) FEI Quanta 200 FEG SEM

10. KUAS Chemical Engineering Bionic technology Lab -Experiment- SiO2表面與3 -氨丙基三乙氧基矽烷（APTS），形成了 NH 2自由基，而三甲氧基矽烷反應合成微矽粉表面，形成環氧化物自由基的表面，在乙醇溶液浴混合，以形成一個層次二氧化矽結構的微矽粉。 在無機化學和物理的製造技術，購買商業二氧化矽粒子的平均直徑 40納米 圖1 (a) organic attachment (b) inorganic route, and physicalbinding

11. KUAS Chemical Engineering Bionic technology Lab -Experiment- Method 1. Organic attachment Method 2. Inorganic route Method 3. Physical binding

12. KUAS Chemical Engineering Bionic technology Lab -Experiment-Method 1. Organic attachment Tetraethoxysilane (TEOS) organic solvents (methanol, ethanol) ammonia solution amine and epoxy end groups coat of PDMS

13. KUAS Chemical Engineering Bionic technology Lab -Experiment-Method 1. Organic attachment The red labels on the right column indicate the precursor chemicals The blue labels on the left column indicate the linking reactions 圖2detailed molecular structure and linking reactions illustrated 

14. KUAS Chemical Engineering Bionic technology Lab -Experiment-Method 2. Inorganic attachment TEOS, ethanol, and deionizedwater mixed hydrochloric acid modify the pH (IEP) as the reaction catalyst mixed in a 1:4:20 ratio phenyltrimethoxysilane in ethanol 5% weigh  immersed in the solution for 8 hFinally dried 50 °C 30 min.  first dried 80 °C 40 min 200 °C 90 min

15. KUAS Chemical Engineering Bionic technology Lab -Experiment-Method 2. Inorganic attachment The red labels on the right column indicate the precursor chemicals The blue labels on the left column indicate the linking reactions 圖3detailed molecular structure and linking reactions illustrated 

16. KUAS Chemical Engineering Bionic technology Lab -Experiment-Method 3. Physical binding three particle loadsthreeparticle loads high temperature diffusional( <700 °C) 4 h coat of PDMS

17. KUAS Chemical Engineering Bionic technology Lab -Experiment-Method 3. Physical binding The red labels on the right column indicate the precursor chemicals The blue labels on the left column indicate the linking reactions 圖4detailed molecular structure and linking reactions illustrated 

18. KUAS Chemical Engineering Bionic technology Lab -Results & Discussion- 1.Particle load 2.Efficiency of contact angle vs optical transmittance 3.Mechanical stability

19. KUAS Chemical Engineering Bionic technology Lab -Results & Discussion-Particle load 圖5Contact angles and transmittance spectra in the visible region for : (a)organic relationship.attachment, (b) inorganic route, (c) physical binding samples, in increasing particle loads.

20. KUAS Chemical Engineering Bionic technology Lab -Results & Discussion- Efficiency of contact angle vsopticaltransmittance 1.Two fabrication methods shared a close resemblance in the position of the curvature 2. DS series have demonstrated a significant improvement in the efficiency of contact angle vs optical transmittance relationship.

21. KUAS Chemical Engineering Bionic technology Lab -Results & Discussion- Efficiency of contact angle vs optical transmittance 圖6Contact angles for each sample are plotted against their average opticaltransmittance

22. KUAS Chemical Engineering Bionic technology Lab -Results & Discussion- Efficiency of contact angle vs optical transmittance 圖7High magnification images of sample surfaces on (a) RB, (b) SG, and (c) DS.

23. KUAS Chemical Engineering Bionic technology Lab -Results & Discussion-Mechanical stability 1.It is not able to judge the degree ofsurface damage given interface adhesionbetween the coatingmaterial and substrate surface. 2.It is recommended an environmentalsimulation or long term outdoor testing to determine the deteriorationof contact angle over time.

24. KUAS Chemical Engineering Bionic technology Lab -Conclusions- 1.contact angle and optical transmittance, in inverse relationships. 2. DS-1 had a contact angle of 166° with 71% optical transmittance. 3. The physical sintering technique is optimistic in producing 150° contact angle with 70%-plus optical transmissivity.

25. KUAS Chemical Engineering Bionic technology Lab -References- [1]Li-Der Liu , Chao-Sung Lin, MukulTikekar, Ping-Hei Chen, Thin Solid Films 519 (2011) 6224–6229. [2]Barthlott and Neinhuis, Planta, 1997, 202, 1.

26. Bionic technology Lab Thank you for your kind attention KUAS Chemical Engineering