Total removal of organic mercury in industrial wastewater is a crucially important task facing environmental pollution in the current world. Herein, we demonstrate the fabrication of Au-NiFe layered double hydroxide (LDH)/rGO nanocomposite as not only an efficient nanozyme with oxidase-like activity but also an efficient surface-enhanced Raman spectroscopy (SERS) substrate to determine organic mercury, with the minimum detection concentration as low as 1 × 10⁻⁸ M. According to the binding energy of X-Ray photoelectron spectrometer (XPS) and the free radicals of electron paramagnetic resonance (EPR) spectra, the mechanism of catalytic enhanced degradation is the production of Au-amalgam on Au surface, accelerating the electron transfer and the generation of O₂^•– radicals from oxygen molecules and •CH₃ radicals from the methyl group in MeHg to participate the oxidase-like reaction. Furthermore, the Au-NiFe LDH/rGO nanocomposite is able to degrade and remove 99.9% of organic mercury in two hours without the secondary pollution by Hg²⁺. In addition, the material can be used for the multiple degradation-regeneration cycles in actual applications, which is significant in terms of the environmental and economic point of view. This work may open a new horizon for both highly sensitive detection and thorough degradation of organic mercury in environmental science and technology.

工业废水中有机汞的完全去除是当前世界面临的环境污染的至关重要的任务。在这里，我们证明了Au-NiFe层状双氢氧化物（LDH）/ rGO纳米复合材料的制备不仅是一种具有氧化酶样活性的有效纳米酶，而且是一种用于测定有机汞的有效表面增强拉曼光谱（SERS）底物。最低检测浓度低至1×10 ^-8M  。根据X射线光电子能谱仪（XPS）的结合能和电子顺磁共振（EPR）光谱的自由基，催化增强降解的机理是产生Au表面上的Au-汞齐，加速电子转移和O ₂ ^•-的生成从氧分子和•CH基团_3组从甲基汞甲基基团的基团参加的氧化酶样反应。此外，Au-NiFe LDH / rGO纳米复合材料能够在两个小时内降解并去除99.9％的有机汞，而不会受到Hg ²⁺的二次污染。另外，该材料可以在实际应用中用于多个降解-再生循环，这在环境和经济角度而言很重要。这项工作可能为环境科学和技术中高度灵敏的检测和彻底降解有机汞开辟新的视野。