Abstract In this work, a unique network core-shell structure based poly(Pyrrole-co-O-Toluidine) (PPCOT) - NiFe2O4 (NF) nanoparticles (NPs) and decorated with cross-linked single-walled carbon nanotubes (C-SWCNTs) has been synthesized as an electrochemical sensor for Fe3+ ions. The results revealed that the electrochemical properties and sensitivity of the ternary PPCOT/NF/C-SWCNT nanocomposites (NCs) were considerably better than the individual properties of copolymer PPCOT, binary PPCOT/NF NCs or NF NPs. The improved properties were attributed to the 3D structure of C-SWCNTs, which offer a large specific surface area that improves the electrical conductivity of the ternary PPCOT/NF/C-SWCNT NCs. DFT calculations for the heat of formation of monomers (PT, PP and TT) were also carried out. The heats of formation of the standard states of the monomers are exothermic and spontaneous at all temperatures. Here, the NCs of the synthesized 3D network core-shell were coated on a working electrode of an electrochemical sensor; the current collector is a glassy carbon electrode. The fabricated sensor is displayed good sensitivity and lower limit of detection of 11.0158 μA μM−1 cm−2 and 97.08 ± 4.85 pM, respectively. By the increasing of PPCOT, it is significantly increased the electrochemical interactions among the matrices of PPCOT, C-SWCNTs and NF. The Fe3+ sensor showed a preference towards Fe3+, which was linear for concentrations ranging from 0.1 nM to 0.01 mM. Moreover, the sensor’s analytical parameters, such as reproducibility and response time, were outstanding. Thus, the assembled sensor is highly effective and useful for Fe3+ ions detection in real environmental samples.

中文翻译：

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三元核壳 PPCOT/NiFe2O4/C-SWCNTs 纳米复合材料的网络设计。选择性 Fe3+ 离子传感器

摘要 在这项工作中，一种基于聚（吡咯-co-O-甲苯胺）（PPCOT）-NiFe2O4（NF）纳米粒子（NPs）并用交联单壁碳纳米管（C-SWCNTs）装饰的独特网络核壳结构) 已被合成为 Fe3+ 离子的电化学传感器。结果表明，三元 PPCOT/NF/C-SWCNT 纳米复合材料 (NCs) 的电化学性能和灵敏度明显优于共聚物 PPCOT、二元 PPCOT/NF NCs 或 NF NPs 的单独性能。改进的性能归因于 C-SWCNTs 的 3D 结构，它提供了大的比表面积，提高了三元 PPCOT/NF/C-SWCNT NCs 的导电性。还进行了单体（PT、PP 和 TT）形成热的 DFT 计算。单体标准态的形成热在所有温度下都是放热和自发的。在这里，合成的 3D 网络核壳的 NC 被涂覆在电化学传感器的工作电极上；集电器为玻碳电极。制造的传感器显示出良好的灵敏度和检测下限分别为 11.0158 μA μM-1 cm-2 和 97.08 ± 4.85 pM。通过增加 PPCOT，显着增加了 PPCOT、C-SWCNTs 和 NF 基质之间的电化学相互作用。Fe3+ 传感器显示出对 Fe3+ 的偏好，对于 0.1 nM 到 0.01 mM 的浓度范围是线性的。此外，传感器的分析参数，如再现性和响应时间，也非常出色。因此，