【摘要】 寻找高活性、碱性稳定且具有极低过电位的非贵金属基析氧反应（OER）催化剂有巨大的价值,但由于OER缓慢的动力学,使其商业化面临相当大的挑战.本文中,我们通过一种自适应的表面重构方法设计了一种强耦合核壳纳米结构的预催化剂.该预催化剂由内部生长的Ni₃N/Ni异质结构核和超薄Ni₃N壳（Ni₃N/Ni@Ni₃N）组成,通过逐步的热氮化路径合成.Ni₃N/Ni@Ni₃N样品在电流密度10 mA·cm^-2下展现出超低的过电位（229 mV）,其在过电位270 mV下,电流密度为单独的Ni₃N、Ni以及商业RuO₂催化剂的17,37和20倍,同时具有较低的塔菲尔斜率(55 mV·dec^-1).在OER过程中,Ni₃N/Ni@Ni₃N样品的表面发生了重构,生成了高活性的NiOOH.原位拉曼光谱和非原位电子显微镜的研究证实了这一点.密度泛函理论（DFT）计算结果表明,NiOOH到Ni₃N的界面电子转移产生了带正电的Ni阳离子,大大降低了OER中间产物吸附/脱附的能垒.更多还原

【Abstract】 Searching for highly active,alkaline-stable and low-cost non-noble metal-based oxygen evolution reaction （OER） catalysts with disruptively low overpotential and outstanding overall performance is of great value and yet faces considerable challenge,due to the sluggish OER kinetics reported for almost all known materials systems.To accelerate the sluggish OER kinetics by a self-adaptive surface reconfiguration approach,we have purposely designed a strongly coupled core@shell nanostructured precatalyst consisting of an in-grown Ni₃N/Ni heterostructured core and an ultrathin Ni₃N shell （Ni₃N/Ni@Ni₃N） via a step-by-step thermal nitridation route.The Ni₃N/Ni@Ni₃N thus-obtained delivers an ultralow overpotential （η） of 229 mV at 10 mA·cm^-2,with the remarkable 17-,37-and 20-fold enhancements in catalytic current density per active surface area at η=270 mV,compared favorably to the individual Ni₃N and Ni alone as well as the commercial RuO₂,respectively,together with a much reduced Tafel slope of 55 mV dec^-1.A self-adaptive surface reconfiguration in Ni₃N/Ni@Ni₃N takes place,by forming highly active NiOOH during the OER process.It is confirmed by the studies of both the in-situ Raman spectrometry and ex-situ electron microscopy.The density functional theory （DFT） calculations demonstrate that the interfacial electron transfer from NiOOH to Ni₃N produces positive-charged Ni cations as the highly active sites to substantially lower the energy barriers for adsorption/desorption of the OER intermediates.更多还原