本實驗室先前發現具推電子官能基的4-乙炔基苯氨修飾在氧化亞銅表面時，會促進正立方體、正八面體、菱形十二面體對於甲基橙染料降解的活性，尤其是正立方體從原先的無降解活性變成有很好的降解活性。而本次實驗拓展至修飾拉電子官能基的4-硝基乙炔苯的氧化亞銅粒子以造成甲基橙染料降解活性的改變。本實驗中使用預處理過的碳酸鉀來催化整個官能化反應。傅立葉轉換紅外光光譜儀和X光射線電子能譜儀的鑑定發現鹼對於炔官能化在氧化亞銅的量可以有效的提升。{100}、{110}及{111}晶面在甲基橙光降解上都有非常顯著的提升，立方體在10分鐘降解了90%，正八面體則在35分鐘降解了90%，菱形十二面體則在5分鐘左右達到99%的降解。之後使用EPR分析於光降解實驗中所產生的各式自由基，並利用三氧化鉻以及草酸鈉分別作為電子電洞捕捉劑。EPR以及電子電洞捕捉劑的實驗顯示，電洞為修飾後的氧化亞銅在光催化中的主要參與反應激子。密度泛函理論計算之結果發現分子修飾會在氧化亞銅的能隙中產生一新的能帶以幫助電子的轉移，使得晶體表面的電荷密度會降低而有較多電洞聚集或產生，以利於電洞轉移至水分子產生氫氧自由基來降解甲基橙。因此用4-乙炔基苯氨修飾在氧化亞銅表面是非常成功的晶體表面改質方法以增強電荷傳輸的例子。

Previously, inactive Cu2O cubes modified with electron-donating conjugated 4-ethynylaniline show a surprisingly high photocatalytic activity. Other particle shapes also displayed enhanced activity. This study explores electron-withdrawing 4-nitrophenylacetylene (4-NA) to reduce the surface charge density and change the photocatalytic activity of Cu2O crystals. The rates of methyl orange photodegradation dramatically improve for the 4-NA-modified Cu2O cubes, octahedra, and rhombic dodecahedra. A base was added to ensure terminal alkyne anchoring on the metal oxide surface. FT-IR spectroscopy and XPS spectra confirm alkyne group of 4-NA literally binding onto the Cu2O surface and addition of a base indeed increases the amount of 4-NA decoration. EPR experiments further verified the occurrence of photocatalytic charge transport process in the functionalized Cu2O crystals. Electron and hole scavenger experiments showed that holes play a greater role in the MO photodegradation, attributed to the electron-withdrawing 4-NA to withdraw the surface electrons to the nitrophenyl group and produce a charge-deficient surface. A new 4-NA-derived band within the band gap revealed density functional theory (DFT) calculations offer a facile pathway for electron transfer to 4-NA and form a charge-deficiency surface for hole transfer to adsorbed water to produce hydroxyl radicals.

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