College of Chemistry and Chemical Engineering, Anhui University, Hefei 230601, China.
Department of Chemical Engineering, Hefei Normal University, Hefei 230601, China.
Molecules. 2023 Jul 3;28(13):5183. doi: 10.3390/molecules28135183.
At present, it is still a challenge to prepare multifunctional composite nanomaterials with simple composition and favorable structure. Here, multifunctional FeO@nitrogen-doped carbon (N-C) nanocomposites with hollow porous core-shell structure and significant electrochemical, adsorption and sensing performances were successfully synthesized through the hydrothermal method, polymer coating, then thermal annealing process in nitrogen (N) and lastly etching in hydrochloric acid (HCl). The morphologies and properties of the as-obtained FeO@N-C nanocomposites were markedly affected by the etching time of HCl. When the FeO@N-C nanocomposites after etching for 30 min (FeO@N-C-3) were applied as the anodes for lithium-ion batteries (LIBs), the invertible capacity could reach 1772 mA h g after 100 cycles at the current density of 0.2 A g, which is much better than that of FeO@N-C nanocomposites etched, respectively, for 15 min and 45 min (948 mA h g and 1127 mA h g). Additionally, the hollow porous FeO@N-C-3 nanocomposites also exhibited superior rate capacity (950 mA h g at 0.6 A g). The excellent electrochemical properties of FeO@N-C nanocomposites are attributed to their distinctive hollow porous core-shell structure and appropriate N-doped carbon coating, which could provide high-efficiency transmission channels for ions/electrons, improve the structural stability and accommodate the volume variation in the repeated Li insertion/extraction procedure. In addition, the FeO@N-C nanocomposites etched by HCl for different lengths of time, especially FeO@N-C-3 nanocomposites, also show good performance as adsorbents for the removal of the organic dye (methyl orange, MO) and surface-enhanced Raman scattering (SERS) substrates for the determination of a pesticide (thiram). This work provides reference for the design and preparation of multifunctional materials with peculiar pore structure and uncomplicated composition.
目前，制备组成简单、结构优良的多功能复合纳米材料仍然是一个挑战。在这里，通过水热法、聚合物涂层、然后在氮气（N）中进行热退火处理以及最后在盐酸（HCl）中进行蚀刻，成功合成了具有中空多孔核壳结构且具有显著电化学、吸附和传感性能的多功能 FeO@氮掺杂碳（N-C）纳米复合材料。所获得的 FeO@N-C 纳米复合材料的形貌和性能明显受到 HCl 蚀刻时间的影响。当蚀刻 30 分钟的 FeO@N-C 纳米复合材料（FeO@N-C-3）用作锂离子电池（LIBs）的阳极时，在 0.2 A g 的电流密度下经过 100 次循环后可达到 1772 mA h g 的可逆容量，明显优于分别蚀刻 15 分钟和 45 分钟的 FeO@N-C 纳米复合材料（948 mA h g 和 1127 mA h g）。此外，中空多孔 FeO@N-C-3 纳米复合材料还表现出优异的倍率容量（在 0.6 A g 时为 950 mA h g）。FeO@N-C 纳米复合材料具有优异的电化学性能，归因于其独特的中空多孔核壳结构和适当的 N 掺杂碳涂层，可为离子/电子提供高效传输通道，提高结构稳定性并适应在反复的 Li 插入/提取过程中的体积变化。此外，用 HCl 蚀刻不同时间的 FeO@N-C 纳米复合材料，特别是 FeO@N-C-3 纳米复合材料，作为去除有机染料（甲基橙，MO）的吸附剂和表面增强拉曼散射（SERS）基底用于测定农药（福美双）也表现出良好的性能。这项工作为设计和制备具有特殊孔结构和简单组成的多功能材料提供了参考。
