氧析出 (OER) 以及氧還原 (ORR) 雙功能活性材料做為可再生燃料電池和金屬空氣電池的電極材料，在近幾年來受到越來越多的關注。雖然在OER有 RuO2、 IrO2 ; 在ORR有 Pt/C 等穩定且高效的催化劑存在。然而，這些貴金屬材料的稀缺性以及昂貴價格，使其在實際應用方面沒有辦法量產，因此便宜的替代材料便顯得至關重要。而在過渡金屬氧化物、氫氧化物，磷化物與硫化物等材料之中，硫化物以出色的導電性以及催化性質成為了最受矚目的替代之一。
在這項研究中，一系列過渡金屬元素（Ti、V、Cr、Mn、Co、Cu、Zn）被系統性地摻雜到鎳鐵硫化物 (NiFe Sulfides) 中，並研究其對其雙功能催化性質所產生的影響。其中，釩原子摻雜的鎳鐵硫化物得益於釩原子帶來的高 Fe3+/ Fe2+比例以及豐富高效的電子轉移，表現出了最佳的ORR催化能力和具有競爭力的OER活性。除此之外，釩原子摻雜鎳鐵硫化物隨後與碳混合後展現出優異的 OER (E10 = 1555 mV) 和 ORR (E1/2 = 769 mV) 催化性質，擁有最小的ΔE值 (E10-E1/2 ) 786 mV。本實驗為透過元素摻雜來優化鎳鐵硫化物的電子結構向的研究提供一些更深的見解。

The development of highly active and nonprecious electrocatalysts for improving the sluggish processes of OER and ORR are essential to the practical application of unitized regenerative fuel cell and metal-air batteries, yet remains a challenge. In this study, a series of transition metals (Ti, V, Cr, Mn, Co, Cu, Zn) have been systematically doped into Nickel Iron Sulfide and studied for better bifunctionality. Among them, Vanadium doped Nickel Iron Sulfide demonstrates the best ORR catalytic ability as well as competitive OER activity, benefitting from the enhanced Fe3+/ Fe 2+ ratio as well as rich and efficient electron transfer brought by Vanadium atoms. Moreover, NFV Sulfide is then physically mixed with carbon and tested in 0.1 M KOH, exhibiting outstanding catalytic ability of OER (E10 = 1555 mV) and ORR (E1/2 = 769 mV), providing the smallest ΔE (E10-E1/2) of 786 mV. This work gives an efficient method for engineering the electronic structure of Nickel Iron Sulfide through optimized doping controlling.

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