Controlled growth of BiFeO3 nanoparticles in the presence of alginate template for adsorptive removal of different dyes

Abstract

In this work, magnetic BiFeO3 nanoparticles were successfully grown via biotemplated method utilizing complex polysaccharides, namely alginate (brown algae). The proportion impact of Bi:Fe molar ratio, weight percent of sodium alginate, pH, and calcination temperature on the phase structure, microstructure, and morphologies of the BiFeO3 nanoparticles were studied using X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. XRD analysis confirmed the formation of a pure phase of BiFeO3 nanoparticles with a rhombohedral structure in the presence of 0.5 wt. % of sodium alginate, Bi:Fe molar ratio of 1:2, at pH 8 and calcination temperature of 550 °C for 2 h. This work suggests that alginate provides a well-defined, chemically and thermally stable environment for the formation of nanoparticles. The biosynthesized BiFeO3 nanoparticles were subsequently evaluated for the removal of methylene blue (cationic), neutral red (neutral), and methyl orange (anionic) dyes. However, they were effective for removing methylene blue and neutral red dyes, but had low efficiency in removing methyl orange dye. The facile and green route approach will render new opportunities for advanced nanomaterials as tremendous potential in environmental remediation for water treatment.