Pomegranate-like MnO2@PANI sub-microspheres: Synthesis and application for Pb(II) ions removal from water

Abstract

Pomegranate-like MnO2@polyaniline (PANI) sub-microspheres have been designed and successfully synthesized as a novel and highly effective sorbent material to remove heavy metal ions from water. Herein, pomegranate-like SiO2@PANI spheres were firstly fabricated by performing the oxidation polymerization of aniline in silica colloidal solution, followed by the removal of SiO2 and in situ redox reaction between KMnO4 and PANI. Compared with the mono-component PANI and MnO2 materials, the obtained pomegranate-like MnO2@PANI sub-microspheres exhibited superior adsorption ability towards Pb(II) ions due to the synergistic effect. Influencing factors, including pH, Pb(II) ions concentration, adsorbents content and other ions on the Pb(II) ion sorption onto the MnO2@PANI hybrid were systematically studied. The sorption isotherm, kinetics and thermodynamic properties of the hybrids for Pb(II) ions adsorption were reflected by different models. Moreover, the adsorption ability of pomegranate-like MnO2@PANI sub-microspheres towards other heavy metal ions was also explored. This work would provide new insight on the design of hierarchical inorganic/organic nanosorbent.