Fabrication, characterization, spectroscopic, and magnetic properties of polyaniline/magnetite (PANi/Fe3O4) nanocomposites

Abstract

In this research, pure polyaniline (PANi), pure magnetite (Fe3O4), and then PANi/ Fe3O4 nanocomposites were prepared and characterized. FT-IR spectra of the prepared samples indicate successful polymerization of PANi onto Fe3O4. PANi/Fe3O4 nanocomposites exhibit broad absorption bands at specific wavenumbers, indicating the presence of various functional groups. The observed blue shift in certain peaks suggests the interaction between nitrogen atoms and oxygen atoms on the magnetite surface through hydrogen bonding. The intensity and wavenumber of the Fe3O4 band decrease, indicating weakened Fe–O bonds. These findings demonstrate a strong interaction and combination between PANi and Fe3O4 in the nanocomposites. Fe3O4 nanoparticles exhibit a regular spherical shape with an average diameter of 16 nm. However, they also show non-uniform size distribution due to aggregation into larger secondary particles, likely driven by attractive forces. PANi/Fe3O4 core-shell nanocomposites demonstrate clear morphological changes, with Fe3O4 nanoparticles well spread and wrapped by the PANi shell. The electron diffraction technique confirms the crystalline structure of Fe3O4 nanoparticles, showing diffraction rings consistent with magnetite. The results confirm the potential of incorporating magnetic Fe3O4 nanoparticles to impart magnetic functionality in the resulting PANi-based nanocomposite materials. Magnetic saturation measurements displayed an enhancement in magnetization with increasing Fe3O4 nanoparticles. The change in magnetic behavior for doped samples provides a means of tuning the magnetization strength of the composites to meet the application requirement such as data storage and magnetic sensors.