Herein, Co₃O₄ nanoparticles deposited on montmorillonite (Co₃O₄–MMT NPs) were synthesized via a facile method and characterized by energy-dispersive X-ray spectroscopy (EDS), powder X-ray diffraction (XRD), and transmission electron microscopy (TEM). Significantly, the as-prepared Co₃O₄–MMT NPs were demonstrated to possess an intrinsic peroxidase-like activity, which could rapidly catalytically oxidize the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine (TMB·2HCl) by H₂O₂, accompanied by a visible color change (colorless to blue); these NPs were then used to develop a sensitive colorimetric sensor for the detection of H₂O₂. The catalytic reaction of Co₃O₄–MMT NPs followed the Michaelis–Menten kinetics equation, and the composites showed good affinity towards TMB. Via the proposed method, H₂O₂ can be detected in the range of 10–100 μM with a low detection limit (DL) of 8.7 μM. Fluorescence data reveal that electron transfer among the catalyst, TMB, and H₂O₂ may contribute to the peroxidase-like activity of the Co₃O₄–MMT NPs. Finally, a colorimetric method was proposed for the detection of H₂O₂, and the robustness of the Co₃O₄–MMT NPs was quite good. The sensor of H₂O₂ based on Co₃O₄–MMT NPs can exhibit great potential applications in the medical, food, and environmental fields.

中文翻译：

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基于Co ₃ O ₄ –具有过氧化物酶活性的蒙脱土纳米复合材料 的H ₂ O ₂比色传感器†

这里，钴₃ ö ₄沉积在蒙脱土（钴纳米颗粒₃ ö _4周-MMT的NP）的合成通过一种容易的方法和其特征在于，能量色散X射线光谱（EDS），粉末X射线衍射（XRD）和透射电子显微镜（TEM）。值得注意的是，所制备的Co ₃ O ₄ -MMT NPs具有固有的过氧化物酶样活性，可以通过H迅速催化氧化过氧化物酶底物3,3'，5,5'-四甲基联苯胺（TMB·2HCl）₂ O ₂，伴随着可见的颜色变化（从无色到蓝色）；然后将这些NP用于开发灵敏的比色传感器，以检测H ₂ O ₂。Co ₃ O ₄ -MMT NPs的催化反应遵循Michaelis-Menten动力学方程，并且复合材料对TMB表现出良好的亲和力。通过提出的方法，可以在10-100μM的范围内检测到H ₂ O ₂，而检测限（DL）仅为8.7μM。荧光数据表明，催化剂，TMB和H ₂ O ₂之间的电子转移可能有助于Co ₃ O ₄的过氧化物酶活性。–MMT NP。最后，提出了一种比色法检测H ₂ O ₂，Co ₃ O ₄ -MMT NPs的鲁棒性很好。基于Co ₃ O ₄ –MMT NP的H ₂ O ₂传感器在医疗，食品和环境领域具有广阔的应用前景。