產學界需要疏水與耐用的材料來因應廣泛的應用之需求。二氧化鈰是天然疏水材料且屬於稀土氧化物（REOs）之一。因為二氧化鈰具有獨特的電子結構，在外殼中是完整的八隅體電子結構，因此二氧化鈰不易於水分子交換電子。以阻擋與周圍環境的水分子交互作用。但是，常見的鎂合金往往是親水的，例如AZ91D鎂合金。此為鎂合金耐腐蝕性能差的原因。這也限制了鎂合金在產業界中的應用，而於鎂合金表面披覆鍍膜為改善其提升抗腐蝕性方式之一。
在這項研究中，透過常壓電漿噴射束以前驅物六水合硝酸鈰、六水合硝酸鈰結合葡萄糖於AZ91D鎂合金的表面上沉積具有抗腐蝕與疏水性的二氧化鈰薄膜，而後透過旋轉塗佈1H，1H，2H，2H-全氟辛基三乙氧基矽烷（FAS-13）於二氧化鈰薄膜表面。膜層材料特性分析透過場發射掃描電子顯微鏡（FE-SEM）進行表面形貌觀測、薄膜附著性透過附著性測試、動電位極化曲線試驗，電化學阻抗譜(EIS)進行抗腐蝕分析、5wt% 鹽霧測試最後水滴接觸角分析。
結果顯示透過常壓電漿沉積二氧化鈰薄膜具有疏水性(127O)與低表面能與優化AZ91D鎂合金抗腐蝕性之特性。而後於二氧化鈰表面上旋轉塗佈上FAS-13後AZ91D鎂合金擁有更佳的疏水接觸角與抗腐蝕性。此研究說明，透過常壓電漿噴射束沉積二氧化鈰膜層與FAS-13與二氧化鈰複合膜層，實現了於AZ91D鎂合金提升表面之疏水性與其抗腐蝕性之表現。

Hydrophobic and durable materials are needed in a broad range of applications. Ce-rium is nature hydrophobic material and one of rare-earth oxides (REOs). Cerium has a unique electronic structure which is full octet of electrons in the outer shell therefore ce-rium has low chance to exchange electron with water molecule. It means cerium can shield from interactions with surrounding environment. However, we know that common magnesium alloys tend to be hydrophilic, such as AZ91D magnesium. This is why mag-nesium alloy has poor corrosion resistant performance, restricting their applications in in-dustry. Coating on surface of magnesium alloy is manner to improve corrosion perfor-mance of magnesium alloy.
In this study a cerium layer which is anticorrosion and hydrophobicity is fabricated on surface of AZ91D magnesium by atmospheric pressure plasma jet(APPJ) that is low-cost equipment and large-area scanning with Cerium (III) nitrate hexahydrate, mix Cerium (III) nitrate hexahydrate with glucose as precursor to improve corrosion perfor-mance of magnesium alloy, following 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FAS-13) is coated on surface of cerium layer by spin coating. The cerium layer’s charac-teristic is analyzed by surface morphology observed by Field Emission Scanning Electron Microscopy (FE-SEM), adhesion cross-cut test (ACCT), potentiodynamic polarization curve test, Electrochemical Impedance Spectroscopy (EIS), water contact angle(WCA), salt spray test in 5 wt % NaCl solution.
The APPJ-deposited cerium layer has a hydrophobicity surface with water contact angle 127O and low surface energy, optimized anticorrosion performance of AZ91D magnesium alloy, while the FAS-13 coating on the cerium layer sample has higher WCA and better anticorrosion performance, investigated by electrochemical impedance spec-troscopy measurements. There result show cerium layer deposited by APPJ or FAS-13/cerium composite coating for improving the corrosion resistance and the surface properties with hydrophobicity form on surface of AZ91D magnesium alloy is achieved.

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