Li Xiang, Xiong Yan, Duan Ming, Wan Haiqin, Li Jun, Zhang Can, Qin Sha, Fang Shenwen, Zhang Run
School of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China.
State Key Laboratory of Pollution Control and Resource Reuse, Jiangsu Key Laboratory of Vehicle Emissions Control, School of the Environment, Nanjing University, Nanjing 210023, China.
Materials (Basel). 2020 Mar 9;13(5):1241. doi: 10.3390/ma13051241.
For further the understanding of the adsorption mechanism of heavy metal ions on the surface of protein-inorganic hybrid nanoflowers, a novel protein-derived hybrid nanoflower was prepared to investigate the adsorption behavior and reveal the function of organic and inorganic parts on the surface of nanoflowers in the adsorption process in this study. Silk fibroin (SF)-derived and copper-based protein-inorganic hybrid nanoflowers of SF@Cu-NFs were prepared through self-assembly. The product was characterized and applied to adsorption of heavy metal ion of Pb(II). With Chinese peony flower-like morphology, the prepared SF@Cu-NFs showed ordered three-dimensional structure and exhibited excellent efficiency for Pb(II) removal. On one hand, the adsorption performance of SF@Cu-HNFs for Pb(II) removal was evaluated through systematical thermodynamic and adsorption kinetics investigation. The good fittings of Langmuir and pseudo-second-order models indicated the monolayer adsorption and high capacity of about 2000 mg g of Pb(II) on SF@Cu-NFs. Meanwhile, the negative values of Δ r G m ( T ) θ and Δ r H m θ proved the spontaneous and exothermic process of Pb(II) adsorption. On the other hand, the adsorption mechanism of SF@Cu-HNFs for Pb(II) removal was revealed with respect to its individual organic and inorganic component. Organic SF protein was designated as responsible 'stamen' adsorption site for fast adsorption of Pb(II), which was originated from multiple coordinative interaction by numerous amide groups; inorganic Cu(PO) crystal was designated as responsible 'petal' adsorption site for slow adsorption of Pb(II), which was restricted from weak coordinative interaction by strong ion bond of Cu(II). With only about 10% weight content, SF protein was proven to play a key factor for SF@Cu-HNFs formation and have a significant effect on Pb(II) treatment. By fabricating SF@Cu-HNFs hybrid nanoflowers derived from SF protein, this work not only successfully provides insights on its adsorption performance and interaction mechanism for Pb(II) removal, but also provides a new idea for the preparation of adsorption materials for heavy metal ions in environmental sewage in the future.
为了进一步理解重金属离子在蛋白质 - 无机杂化纳米花表面的吸附机制，本研究制备了一种新型的蛋白质衍生杂化纳米花，以研究其吸附行为，并揭示纳米花表面有机和无机部分在吸附过程中的作用。通过自组装制备了丝素蛋白（SF）衍生的铜基蛋白质 - 无机杂化纳米花SF@Cu - NFs。对产物进行了表征，并将其应用于对Pb(II)重金属离子的吸附。所制备的SF@Cu - NFs具有中国牡丹花状形态，呈现出有序的三维结构，并且对Pb(II)的去除表现出优异的效率。一方面，通过系统的热力学和吸附动力学研究评估了SF@Cu - HNFs对Pb(II)的吸附性能。Langmuir模型和准二级模型的良好拟合表明了在SF@Cu - NFs上的单层吸附以及对Pb(II)约2000 mg g的高吸附容量。同时，Δ r G m ( T ) θ和Δ r H m θ的负值证明了Pb(II)吸附的自发和放热过程。另一方面，针对SF@Cu - HNFs对Pb(II)的去除，从其单独的有机和无机成分方面揭示了吸附机制。有机SF蛋白被指定为对Pb(II)快速吸附的负责“雄蕊”吸附位点，这源于众多酰胺基团的多重配位相互作用；无机Cu(PO)晶体被指定为对Pb(II)缓慢吸附的负责“花瓣”吸附位点，这受到Cu(II)强离子键弱配位相互作用的限制。仅约10%重量含量的SF蛋白被证明是SF@Cu - HNFs形成的关键因素，并且对Pb(II)处理有显著影响。通过制备源自SF蛋白的SF@Cu - HNFs杂化纳米花，这项工作不仅成功地提供了关于其对Pb(II)去除的吸附性能和相互作用机制的见解，而且为未来环境污水中重金属离子吸附材料的制备提供了新的思路。
