隨著目前全球對於能源的需求日益提升，在取得能源的同時對於環境之威脅亦相對地提升，有鑑於此，目前世界各國正極力投入新綠色能源開發的相關研究，其中一種能源就是燃料電池。而燃料電池長久以來被使用大多的白金電極導致價格昂貴。在地球上的資源很稀少，因此開發非白金觸媒也成為近年來的研究趨勢。
而本研究嘗試混合兩種不同金屬(鈷及鐵)前驅物的過渡金屬環大錯合物為非白金觸媒，取代原有的白金觸媒，並且應用於質子交換膜燃料電池中。發現溫度處理過後的觸媒具有極佳的氧還原能力，其電子轉移數可達 3.97，相當接近理想電子轉移數。而在電池總輸出功率的部分可達到 423 mW/cm2，可見此觸媒的優勢。在進行100小時的觸媒穩定度測試後發現，此觸媒穩定度相當良好，開路電壓也可達0.93 V。在結構分析上，發現此混合環氮觸媒在達到最佳熱處理條件時，其外圍會有一層類似石墨層的洋蔥層狀結構，此結構在進行氧還原反應時，可幫助電子傳遞，使觸媒更加導電，氧氣還原活性提升。而由同步輻射光源得到的吸收光譜分析可以知道觸媒在經過熱處理後的價數變化，其中鐵的價數沒有改變，都維持+3價，而鈷的價數會有一部分變為+2價，一部分維持原來的+3價。

With the growth of global energy demand and human impacts on the environment, there is an ever increasing need for each country to come up with a realistic plan for a green energy sources. One of the potential energy sources is fuel cell. Unfortunately, one of the limitations of fuel cell is the use of an expensive catalyst in platinum. Moreover, the resources of platinum in the world are getting scarce. Based on this limitation, developing of a non-platinum based catalyst has become an attractive topic for research in the recent years.
This study attempts to mix two kinds of transition metal (Co and Fe) coming from their respective macrocyclic complexes as the catalyst to replace the platinum. As our model system, we applied the catalyst into a typical proton exchange membrane fuel cell. The mixed catalyst demonstrates good oxygen reduction ability after pyrolysis having an electron transfer number of 3.97, which is very close to the ideal electron transfer number, 4.00. In PEMFC test, the maximum power density attained using the mixed catalyst is 423 mW/cm2. The mixed catalyst also shows good stability after 100 hours with open circuit potential (OCP) maintaining at 0.93 V. From our structure analysis, it can be found that an onion-like graphite shell surrounds the active site and will help electron transfer during oxygen reduction reaction. From x-ray absorption spectroscopy (XAS) data, we found that a change of oxidation state occurs after pyrolysis. The oxidation state of iron (+3) in the mixed catalyst does not change while part of the cobalt change from +3 to +2 after pyrolysis.

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