隨著全球暖化問題日益嚴重，二氧化碳轉化技術的發展備受關注，其中電化學二氧化碳還原反應（CO₂RR）被視為最具潛力的技術之一。本研究結合八乙基紫質（OEP）金屬錯合物與氧化銅（CuO）奈米材料，開發一種可促進多碳產物生成的新型複合催化劑。首先合成銅紫質（CuOEP）及鎳紫質（NiOEP）的溴取代衍生物，並探討結構修飾對催化行為的影響。研究發現，未取代的NiOEP負載於碳材（CB）時，主要生成一氧化碳（FECO = 15%）；然而，導入溴取代基後，反應選擇性轉向析氫反應（HER），顯示過度拉電子效應不利於CO₂RR。 進一步地，將NiOEP與CuO組裝形成複合催化劑後，展現顯著的協同效應，在–1.2 V條件下乙烯（C₂H₄）的法拉第效率可達30%，而HER被有效抑制至22%，相比之下，CuOEP/CuO複合系統對乙烯的選擇性較低（FEC₂H₄ = 16%）。催化劑的光譜與電化學性質經由UV–Vis、循環伏安法（CV）與氣相層析（GC）等技術分析，並於流動式電解槽中（flow cell）進行CO₂RR測試，以模擬實際操作條件。綜合而言，本研究驗證了紫質配體的電子結構對CO₂RR選擇性的影響，並揭示其與CuO奈米材料間的界面協同效應，為設計高效且具多碳產物選擇性的電催化系統提供了理論依據與實驗基礎。;Growing concerns over global warming have intensified efforts to valorize CO₂, with the electrochemical CO₂ reduction reaction (CO₂RR) emerging as a leading strategy. Here, we report a hybrid electrocatalyst that couples octaethyl¬porphyrin (OEP) metal complexes with copper-oxide (CuO) nanomaterials to direct CO₂RR toward multi-carbon products. Copper(II) OEP (CuOEP) and brominated nickel(II) OEP (NiOEP-Br) derivatives were synthesized to probe ligand electronic effects. Pristine NiOEP supported on carbon black (CB) favored CO formation (FE_CO ≈ 15%), whereas NiOEP-Br shifted selectivity toward the competing hydrogen-evolution reaction (HER), confirming that excessive electron withdrawal hinders CO₂RR. Remarkably, a NiOEP/CuO composite displayed pronounced synergy, delivering a 30% Faradaic efficiency for ethylene (FE_C₂H₄) at –1.2 V while suppressing HER to 22%. By contrast, a CuOEP/CuO composite reached only 16% FE_C₂H₄. Catalyst optical and electrochemical properties were elucidated by UV–Vis spectroscopy, cyclic voltammetry, and gas chromatography, and CO₂RR performance was evaluated in a flow-cell electrolyzer to mimic practical conditions. These findings establish the pivotal role of porphyrin electronic structure and its interfacial cooperation with CuO nanomaterials, offering a rational design blueprint for next-generation electrocatalysts that efficiently channel CO₂ toward value-added multi-carbon products.
