High-performance nonprecious electrocatalysts toward water splitting are in high demand but currently their development is still challenging. Here, we demonstrate that heterometallic two-dimensional (2D) metal phosphonates with improved catalytic activity and durability could be realized through defect engineering and heterometallic doping. The optimal electrocatalyst QAU-1-FeNi(1:2) exhibits prominent oxygen evolution reaction (OER) activity in alkaline electrolytes with a very low overpotential of 230 mV at 10 mA cm⁻² and a small Tafel slope of 47 mV dec⁻¹ and is superior to the commercial electrocatalyst IrO₂. Meanwhile, QAU-1-FeNi(1:2) shows outstanding stability for at least 20 hours and continuous CV scanning for more than 2000 cycles. In this work, a novel strategy of optimization of phosphonate based electrocatalysts by defect engineering and heterometallic doping has been proposed, which has significant potential in the preparation of catalysts for energy conversion applications.

中文翻译：

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有缺陷的二维层状异金属膦酸盐作为高效析氧电催化剂

用于水分解的高性能非贵金属电催化剂的需求量很大，但目前它们的发展仍然具有挑战性。在这里，我们证明了通过缺陷工程和异金属掺杂可以实现具有更高催化活性和耐久性的异金属二维 (2D) 金属膦酸盐。最佳电催化剂 QAU-1-FeNi(1:2) 在碱性电解质中表现出显着的析氧反应 (OER) 活性，在 10 mA cm ^{-2 时}具有 230 mV 的极低过电位和 47 mV dec ^-1的小塔菲尔斜率并且优于商业电催化剂IrO ₂. 同时，QAU-1-FeNi(1:2) 表现出出色的稳定性，至少 20 小时，连续 CV 扫描超过 2000 次循环。在这项工作中，提出了一种通过缺陷工程和异金属掺杂优化膦酸酯基电催化剂的新策略，该策略在制备用于能量转换应用的催化剂方面具有巨大潜力。