由於銅在自然界的含量相對豐富並具有柔韌性以及溶液相奈米線塗覆工藝的薄膜具有良好穿透度和低電阻，故溶液合成銅奈米線的透明導電膜具有較高可能性取代氧化銦錫導電膜。然而，熱不穩定性和易氧化性阻礙了銅奈米線的透明導電膜的實際應用。在本文中，我們研究了分散劑（即聚乙烯吡咯烷酮，PVP）對水熱製備的Cu奈米線的影響。對具有/不具有PVP的銅奈米線進行了比較研究。對氧化機制的研究表明，與PVP化學鍵結的銅奈米線很容易形成氧化並使得奈米線的表面易形成氧化物/氫氧化物，影響透明導電電極的穩定性。最後，我們將Cu NWs薄膜表面上簡單塗覆無色聚酰亞胺（CPI）來解決Cu NWs薄膜的氧化問題。研究表明，Cu NWs薄膜有CPI保護層在一般環境條件下能夠存活3個月以上。

Transparent conducting films of solution-processed copper nanowires (Cu NWs) are an attractive alternative to indium tin oxide due to the relative abundance of Cu, moderate flexibility, small sheet resistance, and good transmittance and low cost of solution-phase nanowire coating processes. However, thermal instability and the ease of oxidation hinder the practical applications of Cu NWs films. In this article, we investigate the effect of capping agent (i.e., polyvinylpyrrolidone, PVP) on hydrothermally prepared Cu nanowires. Comparative studies are presented for Cu nanowires dispersed with/without PVP. A study of the oxidation mechanism reveals that the copper nanowires anchored with PVP will easily form surface oxide/hydroxide which are oxide into nanowires and influence stability of transparent conducting electrode. Finally, we also solved the oxidation problem of Cu NWs film by simple coating of colorless polyimide (CPI) on the surface of Cu NWs film. The study revealed that with CPI protecting layer is able to survived longer than 3 months in ambient condition.

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