Abstract Nanotubes of nickel ferrite were prepared by citrate method and were used in nanocomposite synthesis via in situ polymerization technique. The structural and surface morphology characterization was carried out by FTIR, XRD, and SEM techniques. FTIR spectra show the characteristic peaks of benzenoid ring, quinoid ring, and nickel ferrite stretching of tetrahedral and octahedral sites. XRD pattern shows that NiFe2O4 nanotubes has a cubic spinal structure and remains undistorted even after dispersion in polyaniline matrix. The SEM image of 15% wt nanocomposite shows that the polyaniline coated nickel ferrite nanotubes form a length about 100 nm. Furthermore, the DC conductivity shows three steps conductivity feature and among all prepared nanocomposites, 15% wt one shows high conductivity of 1.89 S/cm. This is due to high absorption of activation energy 0.213 × 10−2 J/mol and elongation of nanocomposites chain length which is confirmed from the negative thermal coefficient graph. The VSM study shows the saturation magnetization decrease after formation of polyaniline nanocomposite. The dielectric properties were analyzed by impedance analyzer and it was found that 15% wt nanocomposite shows the lowest dielectric constant and dielectric loss as a result of high ac conductivity of about 1.32 S/cm which is due to sharp drop in bulk resistance and low relaxation time of 0.1375 µsec as evidenced from cole–cole plot.

中文翻译：

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杂化镍铁氧体纳米管掺杂聚苯胺纳米复合材料及其介电性能

摘要 采用柠檬酸盐法制备了铁氧体镍纳米管，并通过原位聚合技术用于纳米复合材料的合成。通过FTIR、XRD和SEM技术进行结构和表面形貌表征。FTIR 光谱显示了四面体和八面体位点的苯环、醌环和镍铁氧体拉伸的特征峰。XRD 图显示 NiFe2O4 纳米管具有立方脊柱结构，即使在聚苯胺基质中分散后也保持不变形。15% wt 纳米复合材料的 SEM 图像显示聚苯胺涂覆的镍铁氧体纳米管形成约 100 nm 的长度。此外，直流电导率显示出三阶电导率特征，在所有制备的纳米复合材料中，15% wt 的一种显示出 1.89 S/cm 的高电导率。这是由于活化能 0.213 × 10-2 J/mol 的高吸收和纳米复合材料链长的延长，这从负热系数图中得到证实。VSM 研究表明形成聚苯胺纳米复合材料后饱和磁化强度降低。通过阻抗分析仪分析介电性能，发现 15% wt 纳米复合材料显示最低的介电常数和介电损耗，这是由于体电阻急剧下降和低弛豫导致的约 1.32 S/cm 的高交流电导率从科尔-科尔图可以看出，时间为 0.1375 微秒。VSM 研究表明形成聚苯胺纳米复合材料后饱和磁化强度降低。通过阻抗分析仪分析介电性能，发现 15% wt 纳米复合材料显示最低的介电常数和介电损耗，这是由于体电阻急剧下降和低弛豫导致的约 1.32 S/cm 的高交流电导率从科尔-科尔图可以看出，时间为 0.1375 微秒。VSM 研究表明形成聚苯胺纳米复合材料后饱和磁化强度降低。通过阻抗分析仪分析介电性能，发现 15% wt 纳米复合材料显示最低的介电常数和介电损耗，这是由于体电阻急剧下降和低弛豫导致的约 1.32 S/cm 的高交流电导率从科尔-科尔图可以看出，时间为 0.1375 微秒。