Chemistry Department, Faculty of Science, Benha University, Benha, Egypt.
Physics Department, Faculty of Science, Benha University, Benha, Egypt.
J Adv Res. 2015 Jul;6(4):555-62. doi: 10.1016/j.jare.2014.01.009. Epub 2014 Jan 27.
Polyaniline-NiFe2O4 nanocomposites (PANI-NiFe2O4) with different contents of NiFe2O4 (2.5, 5 and 50 wt%) were prepared via in situ chemical oxidation polymerization, while the nanoparticles nickel ferrite were synthesized by sol-gel method. The prepared samples were characterized using some techniques such as Fourier transforms infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Moreover, the electrical conductivity and optical properties of the nanocomposites were investigated. Pure (PANI) and the composites containing 2.5 and 5 wt% NiFe2O4 showed amorphous structures, while the one with 50 wt% NiFe2O4 showed a spinel crystalline structure. The SEM images of the composites showed different aggregations for the different nickel ferrite contents. FTIR spectra revealed to the formation of some interactions between the PANI macromolecule and the NiFe2O4 nanoparticles, while the thermal analyses indicated an increase in the composites stability for samples with higher NiFe2O4 nanoparticles contents. The electrical conductivity of PANI-NiFe2O4 nanocomposite was found to increase with the rise in NiFe2O4 nanoparticle content, probably due to the polaron/bipolaron formation. The optical absorption experiments illustrate direct transition with an energy band gap of Eg = 1.0 for PANI-NiFe2O4 nanocomposite.
聚邻苯二胺-镍铁氧体纳米复合材料（PANI-NiFe2O4），不同含量的 NiFe2O4（2.5、5 和 50wt%）通过原位化学氧化聚合制备，而纳米颗粒镍铁氧体则通过溶胶-凝胶法合成。采用傅里叶变换红外光谱（FTIR）、X 射线衍射（XRD）、扫描电子显微镜（SEM）和热重分析（TGA）等技术对制备的样品进行了表征。此外，还研究了纳米复合材料的电导率和光学性能。纯（PANI）和含有 2.5 和 5wt% NiFe2O4 的复合材料表现出非晶结构，而含有 50wt% NiFe2O4 的复合材料则表现出尖晶石晶相结构。复合材料的 SEM 图像显示出不同镍铁氧体含量的不同聚集状态。FTIR 光谱表明 PANI 大分子与 NiFe2O4 纳米颗粒之间形成了一些相互作用，而热分析表明，随着 NiFe2O4 纳米颗粒含量的增加，复合材料的稳定性有所提高。PANI-NiFe2O4 纳米复合材料的电导率随着 NiFe2O4 纳米颗粒含量的增加而增加，这可能是由于极化子/双极化子的形成。光学吸收实验表明，PANI-NiFe2O4 纳米复合材料具有直接跃迁，能隙 Eg=1.0eV。
