Hu Zhongliang, Zhang Xiaojing, Li Jingying, Zhu Yirong
Department of Inorganic Nonmetallic Material, College of Metallurgy and Material Engineering, Hunan University of Technology, Zhuzhou, China.
Front Chem. 2020 Feb 28;8:150. doi: 10.3389/fchem.2020.00150. eCollection 2020.
In this study, two kinds of composites with the structure of graphene oxide (GO) sheets wrapped magnetic nanoparticles were investigated on their regeneration. The composites have a similar core-shell structure, but the interactions between the core and shell are quite different, which are electrostatic and covalent. They were characterized by scanning/transmission electron microscopy, power X-ray diffraction, and vibrating sample magnetometer analysis. Their morphologies and structures of the samples had been revealed using methylene blue and Pb(II) as adsorbates during regeneration. The results showed that the composites with covalent bonding interaction could maintain a stable core-shell structure and present a good regeneration performance for adsorption-desorption of methylene blue and Pb(II). The composites with electrostatic interaction could approximately preserve its core-shell structure and could be recyclable for adsorption-desorption of methylene blue, however, they would disintegrate its core-shell structure during adsorption/desorption of Pb(II), thus greatly decreasing their regeneration performance. The regeneration mechanisms of the composites were analyzed, which could provide a useful theoretical guide to design the GO sheets wrapped magnetic nanoparticles composites.
在本研究中，对两种具有氧化石墨烯（GO）片包裹磁性纳米颗粒结构的复合材料进行了再生研究。这些复合材料具有相似的核壳结构，但核与壳之间的相互作用差异很大，分别为静电相互作用和共价相互作用。通过扫描/透射电子显微镜、粉末X射线衍射和振动样品磁强计分析对它们进行了表征。在再生过程中，以亚甲基蓝和Pb（II）作为吸附质，揭示了样品的形貌和结构。结果表明，具有共价键相互作用的复合材料能够保持稳定的核壳结构，对亚甲基蓝和Pb（II）的吸附-解吸表现出良好的再生性能。具有静电相互作用的复合材料能够大致保持其核壳结构，对于亚甲基蓝的吸附-解吸可循环使用，然而，在Pb（II）的吸附/解吸过程中它们会解体其核壳结构，从而大大降低其再生性能。分析了复合材料的再生机理，可为设计GO片包裹磁性纳米颗粒复合材料提供有用的理论指导。
