尿素氧化反應 (UOR) 是決定現代尿素基能量轉換技術性能的基礎反應。這些技術包括用於產氫的電催化和光電化學尿素分解以及作為動力發動機的直接尿素燃料電池。相較於析氧反應（OER）具有很高的過電位，會顯著降低水分解的能量效率，由於尿素氧化反應 (UOR)具有較低的電極電位，所以使用尿素氧化反應（UOR）代替OER是一種可行且節能的方法，因此可以被當作為當前水分解和氫燃料電池系統替代品的巨大潛力，具有更有利的操作條件和成本效益。不過，目前尿素氧化反應 (UOR) 性能主要受限於6電子轉移過程以及受到CO2吸附而阻絕活性位點的問題。因此，透過各種材料設計和合成策略來改善並合成出具有高效率的 UOR 催化劑。
本研究中，利用添加微量的其他元素並探討各個元素間的交互作用，以NiFe的layer double hydroxide(LDH)為基底，分別加入Ti、V、Zn、Ag、Cr合成三、四元過渡金屬的雙層氫氧化物，採用溶劑熱法合成層狀雙氫氧化物，並透過探討過渡金屬元素之間的協同效應，提升尿素氧化反應 (UOR)的催化活性與穩定性。
為了再更進一步提升催化的性能，本研究亦利用摻雜多元的陰離子概念，透過進一步將層狀雙氫氧化物進行硫化反應，合成多元素之硫化物。並探討其多元金屬及非金屬之間的調節以及在UOR的催化過程中材料表面形貌及鍵結變化的機制以及CO2的催化劑的影響來達到合成出高效能之分解尿素氧化的電催化劑。

The commercial catalyst for urea oxidation reaction (UOR) is noble metal-based catalyst such as RuO2. Although noble metal catalysts have impressive UOR activities, their expensive price, scarcity, and poor long-term stability limit the largescale applications. The requirement of synthesizing effective, and stable nonprecious element based UOR catalysts is high. In this study, first we have synthesized multi-element layer double hydroxide(LDH) using facilely one-step solvothermal process. The catalyst of NFTiCr demonstrates ultra-low potential of 1.32V at current density of 10mA cm-2 in alkaline solution and also much improves the durability. In order to further enhance the electrocatalytic performance, Sulfurization was used to synthesize pure phase multi-element sulfides. NFTiS with higher CO2 affinity exhibits outstanding performance with 1.36V at current density of 100 mA cm-2. These extraordinary UOR performance of the metal-doped LDH and sulfide will have a great opportunity for practical applications.

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