A nFe@ZIF-8 composite, which combined the tailorable porosity of ZIF-8 with the versatile functionality of Fe nanoparticles (nFe), was synthesized for Pb(II) removal. Batch adsorption experiments showed that more than 95.3% of Pb(II) was removed from aqueous solution at an initial concentration of 50 mg L-1 when using nFe@ZIF-8 within 60 min at pH value of 5. The mechanism of Pb(II) removal was studied via characterization of changes the morphology, size and composition of in nFe@ZIF-8 before and after exposure the solutions containing Pb(II). Specifically, Fourier transform infrared (FTIR) and X-ray powder diffraction (XRD) indicated that nFe@ZIF-8 was successfully synthesized and also remained stable after Pb(II) removal. Transmission Electron Microscope (TEM) and Scanning electron microscopy-X-ray energy dispersive spectrometer (SEM-EDS) both confirmed that Pb(II) was partially adhered onto the surface of nFe@ZIF-8, where X-ray photoelectron spectroscopy (XPS) specifically revealed the existence of Pb(0) on the surface. This indicated that Pb(II) was initially adsorbed onto the surface of nFe@ZIF-8 and subsequently reduced to Pb(0). Moreover, Pb(II) removal fit well to kinetics of absorption and reduction. Finally, in practice, nFe@ZIF-8 could remove 96.3% of Pb(II) from an electroplating wastewater.

中文翻译：

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一种新的nFe @ ZIF-8，用于通过选择性吸附和还原去除废水中的Pb（II）。

合成了一种nFe @ ZIF-8复合材料，该复合材料将ZIF-8的可调节孔隙率与Fe纳米颗粒（nFe）的通用功能相结合，用于去除Pb（II）。批量吸附实验表明，当在60 pH值为5的条件下使用nFe @ ZIF-8在60分钟内以50 mg L-1的初始浓度从水溶液中去除了95.3％以上的Pb（II）。 II）通过表征暴露在含Pb（II）溶液之前和之后nFe @ ZIF-8中的形态，大小和组成的变化来研究去除。具体而言，傅立叶红外光谱（FTIR）和X射线粉末衍射（XRD）表明nFe @ ZIF-8已成功合成，并且在去除Pb（II）后仍保持稳定。透射电子显微镜（TEM）和扫描电子显微镜-X射线能量色散光谱仪（SEM-EDS）均证实Pb（II）部分粘附在nFe @ ZIF-8的表面上，在那里X射线光电子能谱（XPS） ）特别揭示了表面上Pb（0）的存在。这表明Pb（II）最初被吸附到nFe @ ZIF-8的表面，随后被还原为Pb（0）。此外，去除Pb（II）非常适合吸收和还原动力学。最后，在实践中，nFe @ ZIF-8可以从电镀废水中去除96.3％的Pb（II）。这表明Pb（II）最初被吸附到nFe @ ZIF-8的表面，随后被还原为Pb（0）。此外，去除Pb（II）非常适合吸收和还原动力学。最后，在实践中，nFe @ ZIF-8可以从电镀废水中去除96.3％的Pb（II）。这表明Pb（II）最初被吸附到nFe @ ZIF-8的表面，随后被还原为Pb（0）。此外，去除Pb（II）非常适合吸收和还原动力学。最后，在实践中，nFe @ ZIF-8可以从电镀废水中去除96.3％的Pb（II）。