Multifunctional magnetic Fe3O4/nitrogen-doped porous carbon nanocomposites for removal of dyes and sensing applications

In this work, a multifunctional magnetic Fe3O4/nitrogen doped-porous carbon nanocomposite (Fe3O4/N-PCNC) with remarkable magnetic, adsorption and catalytic properties was synthesized using naringin as carbon precursor. Characterization studies revealed that Fe3O4/N-PCNC exhibited a mesoporous structure with different functional groups and good magnetic properties. Its applications for the removal of organic dyes as well as the non-enzymatic colorimetric detection of hydrogen peroxide and glucose were investigated. The removal of the organic dyes from water showed that over 99.7% crystal violet and rhodamine B, and 100% thionine with concentrations of ca. 60 mg/L can be removed by Fe3O4/N-PCNC within 15 min. Recovery and recycling studies showed that, after 5 cycles, Fe3O4/N-PCNC, lost only around 2.94%, 3.97% and 3.36% of its initial ability to remove crystal violet, rhodamine B and thionine, respectively. Furthermore, Fe3O4/N-PCNC exhibited intrinsic peroxidase-mimic activity. Fe3O4/N-PCNC was used for colorimetric sensing of hydrogen peroxide and glucose with high sensitivity and low limits of detection of 0.1 µM and 2.6 µM, respectively. The glucose sensor also shows high reproducibility, selectivity and was successfully applied to sense glucose in various drinks. This indicates the promising application potential of Fe3O4/N-PCNC in water treatment, quality analysis and medicine fields. © 2018 Elsevier B.V.