Abstract γ-Fe2O3 nanoparticles were deposited on the surface of multiwalled carbon nanotubes (MWCNT) by atomic layer deposition, followed by polyethyleneimine (PEI) surface modification, and the amine groups on the MWCNT were confirmed by Fourier transform infrared spectroscopy. MWCNT/γ-Fe2O3 samples both with and without PEI surface decoration were used to remove Cr(VI) in water by adsorption. The adsorption results indicate that PEI-decorated MWCNT/γ-Fe2O3 has 42.8% higher adsorption efficiency than MWCNT/γ-Fe2O3 without surface modification, which was attributed to the chelation and complexation of amine groups with Cr(VI). The magnetization from γ-Fe2O3 also contributed to efficient separation of the nanocomposite from solution. Moreover, the adsorption behaviors were also studied by Langmuir and Freundlich isotherm models.

中文翻译：

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γ-Fe2O3 纳米粒子在改性多壁碳纳米管上的原子层沉积以有效吸附水溶液中的 Cr(VI) 离子

摘要 γ-Fe2O3 纳米粒子通过原子层沉积法沉积在多壁碳纳米管（MWCNT）表面，然后进行聚乙烯亚胺（PEI）表面改性，并通过傅里叶变换红外光谱确认多壁碳纳米管（MWCNT）上的胺基团。使用带有和不带有 PEI 表面装饰的 MWCNT/γ-Fe2O3 样品通过吸附去除水中的 Cr(VI)。吸附结果表明，PEI 修饰的 MWCNT/γ-Fe2O3 的吸附效率比未经表面修饰的 MWCNT/γ-Fe2O3 高 42.8%，这归因于胺基团与 Cr(VI) 的螯合和络合。γ-Fe2O3 的磁化也有助于纳米复合材料从溶液中的有效分离。此外，还通过 Langmuir 和 Freundlich 等温线模型研究了吸附行为。