Abstract Composite Co-Mn-Fe oxide catalysts were prepared by thermal decomposition of layered double hydroxide (LDH) or hydrotalcite-like precursors. A series of catalysts at different Mn/Fe ratios were obtained and characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF) spectrometry, UV–vis diffuse reflectance spectroscopy and BET surface area analysis. The catalysts were tested for methylene blue (MB) dye decomposition under visible light illumination with and without the assistance of NaHSO3. When visible light illumination was used on the catalyst in the presence of NaHSO3, the degradation efficiency was greatly enhanced. All the Mn-containing samples showed much higher capability to degrade MB than that of MnO2 under the same conditions. The [0]CoMnFe-LDO sample which did not contain any Mn showed lower degrading ability than MnO2. In addition to determining the role of Mn and the Mn/Fe ratio of the complex oxide catalysts on the decomposition of MB, the stability and reusability of these complex oxide catalysts were also tested and found to be good.

中文翻译：

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来自层状双氢氧化物的 Co-Mn-Fe 复合氧化物催化剂用于分解亚甲蓝：Mn 的作用

摘要 通过层状双氢氧化物（LDH）或类水滑石前驱体的热分解制备复合Co-Mn-Fe氧化物催化剂。获得了一系列不同 Mn/Fe 比的催化剂，并通过 X 射线衍射 (XRD)、X 射线荧光 (XRF) 光谱、紫外-可见漫反射光谱和 BET 表面积分析表征。在可见光照射下，在有和没有 NaHSO3 的帮助下，测试了催化剂的亚甲蓝 (MB) 染料分解。当在 NaHSO3 存在下对催化剂使用可见光照射时，降解效率大大提高。在相同条件下，所有含 Mn 的样品都显示出比 MnO2 更高的降解 MB 的能力。不含任何 Mn 的 [0]CoMnFe-LDO 样品显示出比 MnO2 更低的降解能力。