Characterization of an Environmentally Responsive Organic-Inorganic Hybrid Fe 3 O 4 /SiO 2 /PPy-c Core-Shell Nanocomposite with Magneto-Chromatic Ability for Synergistic Electrical Properties.

The aim of this study was to analyze the properties of a composite that incorporates carbon black and polypyrrole within an Fe 3 O 4 /SiO 2 core-shell structure, synthesized using the Stöber method under high ultrasonic irradiation conditions (120 W) for Fe 3 O 4 /SiO 2 nanocomposite. The Fe 3 O 4 /SiO 2 core-shell indicates magnetochromatic behavior characterized by temperature-dependent coloration and magnetic alignment. Incorporating carbon black and polypyrrole at moderate temperature (5-15 °C) enhanced the electrical conductivity. The electrical resistivity ρ was 7.30 × 10 6 Ω·cm for Fe 3 O 4 , 3.19 × 10 8 Ω·cm for Fe 3 O 4 /SiO 2 , and 242.56 Ω·cm for Fe 3 O 4 /SiO 2 /PPy-c at room temperature. When it was performed at moderate temperature (5-15 °C), the ρ of the prepared Fe 3 O 4 /SiO 2 and Fe 3 O 4 /SiO 2 /PPy-c nanocomposite was 1.08 × 10 8 and 0.00799 Ω·cm, respectively. Current-voltage measurements revealed a linear relationship, with butterfly shaped curves in the forward-bias region for all samples. The Fe 3 O 4 /SiO 2 /PPy-c nanocomposite's tunable synergistic electrical properties at moderate temperatures make it useful for environmental applications, electrical wiring, and circuitry.