Oxygen electrocatalysis is vital for advanced energy technologies, but inordinate challenges remain due to the lack of highly active earth-abundant catalysts. Herein, by nanostructuring and defect engineering, we enhance the catalytic properties of naturally occurring, but normally inactive ore hematite (Ht) by converting it to hematene (Hm) with oxygen vacancies (Ov-Hm), which becomes an efficient oxygen evolution reaction (OER) catalyst, being even superior to the state-of-the-art catalyst IrO₂/C, with a current density of 10 mA cm⁻² at a lower overpotential of 250 mV. First-principles calculations reveal that the reduced dimensionality and defects on the Hm surface locally modify the charge around the adsorption sites, which results in a reduction of the potential barrier in the OER process. Our experimental and theoretical insights suggest a promising route to the development of a highly active electrocatalyst from the naturally occurring and abundant material for OER applications.

中文翻译：

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揭示苏木烯的缺陷占主导地位的放氧活性

氧气电催化法对于先进的能源技术至关重要，但是由于缺乏高活性的富含地球的催化剂，挑战依然严峻。在本文中，通过纳米结构和缺陷工程，我们通过将氧空位（Ov-Hm）转化为he烯（Hm）来增强天然存在但通常不活泼的矿石赤铁矿（Ht）的催化性能，这成为有效的析氧反应（ OER）催化剂，甚至优于最新的催化剂IrO ₂ / C，电流密度为10 mA cm ^-2在250 mV的较低电位下。第一性原理计算表明，Hm表面尺寸的减小和缺陷的发生会局部改变吸附位点附近的电荷，从而导致OER过程中势垒的减小。我们的实验和理论见解提出了从天然存在的丰富的OER应用材料开发高活性电催化剂的有前途的途径。