Abstract
This study investigates the graphene reinforcement in bismuth ferrite (BiFeO3 or BFO) composites by powder metallurgy technique with the goal of enhancing their spectroscopic, physical and electrical properties for multifunctional applications. The powder composites prepared by dry planetary ball milling of 5 hours followed by compaction at 200 MPa and sintering at 850 oC for 6 hours under argon atmosphere. Results revealed a significant enhancement in the properties of composites with increasing graphene content in BFO. BFO is a promising multiferroic material; however, its practical applications are limited due to inherent drawbacks such as low electrical conductivity, rapid charge carrier recombination and limited surface area. The optimized BFO/graphene (1 mol) composite exhibited a substantial reduction (~37% reduction) in energy band gap from 2.62 eV (pure BFO) to 1.63 eV, alongside a high increase (~24-fold increase) in BET surface area from 4.9 m2/g (BFO) to 120 m2/g and a remarkable improvement (a four-order-of-magnitude increase) in electrical conductivity from 5.2 × 10-4 S/cm to 5.65 S/cm. Raman analysis indicated strong interfacial interactions and strain effects between BFO and graphene, which contribute to improved charge separation and transport. These enhancements are attributed to the synergistic effects of graphene’s conductive π-network; the well-dispersed composite structure achieved via powder metallurgy and optimized processing parameters. The study concludes that 1 mol graphene-reinforced BFO is a promising candidate for next-generation applications in energy storage, photocatalysis, sensors and environmental remediation.
Keywords: Bismuth Ferrite, Graphene, Nanocomposite, Powder Metallurgy Technique.