【摘要】 钙钛矿氧化物具有灵活的组成和电子结构,在电催化水氧化反应中具有很大的应用潜力.然而,钙钛矿氧化物在电催化有机小分子转化中的应用研究较少,这可能是由于其导电性差,表面重构产生活性物种所需的能垒高.在本文中,我们报道了具有典型反钙钛矿结构的氮化铜纳米片作为甲醇选择性转化为甲酸盐的电催化剂,其形成甲酸盐的法拉第效率超过90%.原位电化学质谱和原位红外反射吸收光谱进一步证实了制备的氮化铜样品在较宽的电位范围内具有较高的甲酸盐选择性.此外,高分辨率透射电镜、X射线吸收光谱和原位拉曼光谱表明,该催化剂在电催化过程中发生表面重构形成了氧化态铜物种壳,从而提升了其整体甲醇氧化性能,而原始的氮化铜核则利于在催化剂内部的电子传递.本研究不仅为甲醇的高选择性转化提供了一种有意义的方案,而且为有机小分子的电化学转化提供了一种新型的非氧化物钙钛矿材料模型.更多还原

【Abstract】 Perovskite oxides with flexible compositions and electronic structures have great potential for application in electrocatalytic water oxidation reactions.However,few studies have focused on the application of perovskite oxides in electrocatalytic oxidation reactions of organic molecules,probably due to the absence of active species because of the poor conductivity and high energy barrier of the surface reconstruction.Herein,we report Cu₃N nanosheets with a typical antiperovskite structure as electrocatalysts for selectively converting methanol to formate.The as-prepared antiperovskite nitride Cu₃N samples exhibit a Faradic efficiency exceeding 90% for methanol to formate over a wide potential range,which was further confirmed by online electrochemical mass spectrometry and in situ infrared reflectance absorption spectroscopy.Moreover,the high-resolution transmission electron microscopy,X-ray absorption spectroscopy,and in situ Raman spectroscopy results indicate that the core-shell structure formed by generating surface Cu（Ⅱ）species triggers the electrocatalytic methanol oxidation reaction activity,whereas the pristine Cu3N core facilitates the electron transport inside the catalyst during the electrocatalytic process.This study provides a modelable scheme for the highly selective conversion of methanol and introduces a novel nonoxide perovskite material for the electrochemical conversion of small-organic molecules.更多还原