本研究主要探討兩種合成方法的奈米氧化銅粉體；氣相合成CuO-V以及液相析出CuO-P，經由油酸化學改質後在表面形成Cupric oleate錯化物，增強奈米氧化銅-正辛烷懸浮液的分散穩定性。實驗中經由黏度儀的量測比較兩種氧化銅粉體在正辛烷中的分散行為，並且藉由穿透式電子顯微鏡的觀察確認粉體表面油酸層吸附情形，最後利用紅外線光譜儀以及高解析電子能譜儀分析表面特性和化學鍵結。結果顯示CuO-P粉體表面帶有大量的氫氧基提供了與油酸根的反應位置，在表面形成較多的Cupric oleate化學鍵結，因此CuO-P有機懸浮液的分散穩定性遠優於CuO-V。此外，本研究亦根據DLVO理論，計算改質後氧化銅膠體粒子在整個有機分散系統的位能曲線。

Two nano-sized cupric oxide powders, which are synthesized by vapor-phase reaction and aqueous precipitation, are surface-modified with unsaturated oleic acid to form cupric oleate on the surface. This enhances the dispersibility of cupric oxide powders in a non-polar solvent of octane. The cupric oxide powder prepared by aqueous precipitation exhibits much better dispersion in octane than that synthesized by vapor-phase reaction. This is attributed to the presence of larger amounts of hydroxyl groups on the particle surface, forming more cupric oleate and thus enhancing the colloidal stability of the resulting suspension.

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