Synthesis of a morphology controllable Fe3O4 nanoparticle/hydrogel magnetic nanocomposite inspired by magnetotactic bacteria and its application in H2O2 detection

Owing to the shape-dependent catalytic activity of Fe3O4 nanoparticles, controlling their morphology is of great significance. In this work, we propose a simple, nontoxic, water-based strategy for the fabrication of magnetic nanoparticle/hydrogel nanocomposites in which highly crystalline Fe3O4 nanooctahedra can be fabricated in situ within a negatively charged hydrogel matrix. The morphology of the Fe3O4 nanocrystals can be easily tuned by adjusting the crosslinking concentration of the hydrogel. Furthermore, the catalytic activities of the magnetic nanocomposites were studied, and the magnetic nanocomposite loaded with Fe3O4 nanooctahedra exhibited excellent catalytic activity and provided a sensitive response toward H2O2 detection. This scalable approach for the fabrication of magnetic nanocomposites, loaded with morphology controllable Fe3O4 nanoparticles, potentially promotes their applications in biotechnology and environmental chemistry.