The slow kinetics of oxygen evolution reaction (OER) catalysts with a large overpotential restricts the feasibility of electrochemical water splitting. Iron based electrodes are attractive candidates, but elevating their activity faces great challenges in weak intermediate adsorption. Herein, we demonstrated that ultrathin FeP nanosheets with Fe defects on nickel foam (FeP-NS/NF) exhibited a remarkable electrocatalytic oxygen evolution performance. The overpotential of FeP-NS/NF only requires 220 mV to achieve a current density of 10 mA cm^–2 in 1 M KOH solution. Moreover, it possessed excellent durability during the 85 h stability test. Fe defects over ultrathin FeP evidenced by X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR) have been experimentally demonstrated to promote oxygenated intermediate adsorption, which largely reduce the overpotential of OER.

中文翻译：

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超薄FeP纳米片作为电催化水氧化的高效催化剂：促进中间体通过表面缺陷的吸附。

具有大的超电势的放氧反应（OER）催化剂的慢动力学限制了电化学水分解的可行性。铁基电极是有吸引力的候选物，但是提高其活性在弱中间吸附方面面临巨大挑战。在本文中，我们证明了在镍泡沫上具有Fe缺陷的超薄FeP纳米片（FeP-NS / NF）表现出显着的电催化析氧性能。FeP-NS / NF的超电势仅需要220 mV即可达到10 mA cm ^–2的电流密度在1 M KOH溶液中。此外，它在85小时的稳定性测试中具有出色的耐久性。通过X射线光电子能谱（XPS）和电子自旋共振（ESR）证明，超薄FeP上的铁缺陷可促进氧化的中间吸附，从而大大降低OER的过电位。