Abstract Novel Mn3O4-promoted double p−n junction MgAl2O4/CeO2/Mn3O4 heterojunction photocatalyst was constructed by one-step synthesis method and two-step synthesis method. The X-ray powder diffraction, Fourier transform infrared spectrum, X-ray photoelectron spectroscopy, optical and photoluminescence demonstrated that the MgAl2O4/CeO2/Mn3O4 heterojunction photocatalyst was synthesized by the two-step synthesis method comprehends a high crystallinity, charge carrier migration and separation efficiency, and relatively low optical absorption coefficient. The MgAl2O4/CeO2/Mn3O4 heterojunction photocatalysts were efficiently used as simulated sunlight-driven n-n and p-n double junction photocatalyst for the simultaneous degradation of methylene blue (MB) dye. The continuous double p−n junction MgAl2O4/CeO2/Mn3O4 heterojunctions strengthened the function of single n-n or p-n junction and guided the charge carrier migration and separation direction; thus, the oxidation and reduction reactions occur at the active site of spatial separation and prevent the recombination of electrons and holes. The results suggest that the continuous double p−n junction MgAl2O4/CeO2/Mn3O4 heterojunctions are very promising candidate material for enhancing the photocatalytic activity in the photocatalytic degradation of MB dye.

中文翻译：

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MgAl2O4/CeO2/Mn3O4异质结光催化剂的简便制备及光催化活性增强

摘要 采用一步合成法和两步合成法构建了新型Mn3O4促进的双p-n结MgAl2O4/CeO2/Mn3O4异质结光催化剂。X射线粉末衍射、傅里叶变换红外光谱、X射线光电子能谱、光学和光致发光表明，MgAl2O4/CeO2/Mn3O4异质结光催化剂是通过两步合成法合成的，具有高结晶度、载流子迁移和分离的特点。效率和相对较低的光吸收系数。MgAl2O4/CeO2/Mn3O4 异质结光催化剂被有效地用作模拟阳光驱动的 nn 和 pn 双结光催化剂，用于同时降解亚甲蓝 (MB) 染料。连续的双 p-n 结 MgAl2O4/CeO2/Mn3O4 异质结加强了单 nn 或 pn 结的功能，引导了载流子迁移和分离方向；因此，氧化和还原反应发生在空间分离的活性位点并阻止电子和空穴的复合。结果表明，连续双 p-n 结 MgAl2O4/CeO2/Mn3O4 异质结是非常有前途的候选材料，可用于增强 MB 染料光催化降解中的光催化活性。