AbstractThe authors describe the preparation of core/shell composites consisting of Fe3O4 microparticles coated with nitrogen-doped mesoporous carbon. Synthesis was accomplished by simultaneous reduction of template α-Fe2O3 and pyrolysis of a nitrogen-containing poly(ionic liquids). The mesoporous composites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffractometry and adsorption/desorption isotherms. The characterizations prove successful formation of an Fe3O4 core and an outer shell (coating) consisting of nitrogen-doped mesoporous carbon. The material was placed on a glassy carbon electrode and synergistic catalytic effect of of N-doping, the mesoporous, core/shell structure and two types of active sites properties between Fe3O4 core and nitrogen-doped mesoporous carbon shell is shown to result in superior electrochemical activity towards the reduction of hydrogen peroxide. Figures of merit include (a) a sensitivity of 77.1 μA mM−1 cm−2; (b) a linear response over the 50 μM to 33 mM H2O2 concentration range, (c) a 5.9 μM detection limit of (at an S/N ratio of 3), and (d) a low working voltage of −0.4 V (vs. saturated calomel electrode) which makes the method more selective. Graphical abstractElectrochemical method for H2O2 detection based on Fe3O4@nitrogen-doped mesoporous carbon microcapsules core/shell composites (Fe3O4@NMCMs), prepared by the polymerization of the ionic liquids (1-Allyl-3-ethylimidazolium tetrafluoroborate, [AEIm]BF4) monomer (PILs) on the surface of α-Fe2O3 nano-peanuts and then pyrolysis.

中文翻译：

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由涂有氮掺杂介孔碳的 Fe3O4 微粒组成的核/壳微胶囊，用于过氧化氢的伏安传感

摘要作者描述了由掺杂氮的介孔碳包覆的 Fe3O4 微粒组成的核/壳复合材料的制备。合成是通过模板 α-Fe2O3 的同时还原和含氮聚（离子液体）的热解来完成的。通过扫描电子显微镜、透射电子显微镜、X 射线光电子能谱、X 射线衍射和吸附/解吸等温线对介孔复合材料进行了表征。表征证明成功形成了 Fe3O4 核和由掺氮介孔碳组成的外壳（涂层）。将该材料置于玻碳电极上，与 N 掺杂、介孔、核/壳结构以及 Fe3O4 核和掺氮介孔碳壳之间的两种活性位点特性显示出对过氧化氢还原具有优异的电化学活性。品质因数包括 (a) 77.1 μA mM-1 cm-2 的灵敏度；(b) 50 μM 至 33 mM H2O2 浓度范围内的线性响应，(c) 5.9 μM 检测限（信噪比为 3），以及 (d) -0.4 V 的低工作电压（与饱和甘汞电极相比），这使得该方法更具选择性。基于Fe3O4@氮掺杂介孔碳微胶囊核/壳复合材料（Fe3O4@NMCMs）的H2O2检测电化学方法，由离子液体（1-烯丙基-3-乙基咪唑鎓四氟硼酸盐，