Shaldehi Tahereh Jangjooye, Rowshanzamir Soosan
Hydrogen & Fuel Cell Research Laboratory, School of Chemical, Petroleum and Gas Engineering, Iran University of Science and Technology, Narmak, 16846-13114, Tehran, Iran.
Sci Rep. 2024 Jun 20;14(1):14201. doi: 10.1038/s41598-024-61223-y.
Non-precious electrocatalysts as the alternative to Pt have become a hot research area in the last decade due to the suitable catalytic activity in Oxygen reduction reaction (ORR) in electrochemical systems. In this work, the density functional theory calculations were investigated to explore the activity of Fe, Cu, and Fe-Cu atoms supported by N-doped graphene as the ORR electrocatalyst for Oxygen-depolarized cathodes (ODCs). To this end, the ORR mechanism was surveyed in detail in the gas and solvent phases. The results show that the solvent phase leads to a higher overpotential and thermodynamic limiting potential. According to the density of states curves, there are strong interactions between metal atom and substrate that can effectively tune the electronics of catalysts. Bader's analysis confirms that, in addition to the single metal atoms, nitrogen atoms have also played a critical role in charge transfer between substrates and oxygen molecules in ORR. It is also predicted that Fe-Cu@NC SAC exhibits the highest catalytic activity which is consistent with thermodynamic limiting potential and theoretical overpotential of - 0.26 and 0.66 (V vs. SHE), respectively, indicating that this type of catalyst may be a suitable candidate instead of precious metals in oxygen-depolarized cathodes in electrochemical devices.
在过去十年中，由于在电化学系统的氧还原反应（ORR）中具有合适的催化活性，非贵金属电催化剂作为铂的替代品已成为一个热门研究领域。在这项工作中，进行了密度泛函理论计算，以探索由氮掺杂石墨烯负载的铁、铜和铁 - 铜原子作为氧去极化阴极（ODC）的ORR电催化剂的活性。为此，在气相和溶剂相中详细研究了ORR机理。结果表明，溶剂相会导致更高的过电位和热力学极限电位。根据态密度曲线，金属原子与基底之间存在强相互作用，可有效调节催化剂的电子性质。巴德分析证实，除了单个金属原子外，氮原子在ORR中基底与氧分子之间的电荷转移中也起着关键作用。还预测Fe-Cu@NC单原子催化剂表现出最高的催化活性，这分别与-0.26和0.66（V vs. SHE）的热力学极限电位和理论过电位一致，表明这种类型的催化剂可能是电化学装置中氧去极化阴极中替代贵金属的合适候选者。
