Synthesis, characterization of novel CFO-BFO nanocomposites and application in highly adsorptive removal of Pb2+ in water environment

The nanocomposites (NCs) of xCoFe2O4-(1-x)BiFeO3 were successfully synthesized by two-step hydrothermal method for selecting an optimize composition of CB55 (x = 0.5) for highly adsorptive removal of Pb2+ in water environment. The CB55 has uniform dispersion of nanoparticles with high specific surface area (48.5 m2/g), and negatively charged surface (−10.4 mV) in neutral pH environment. A nanocomposite dose of 1.0 g/l of CB55 could remove more than 99%, 95%, and 87% of 10, 25 and 50 ppm Pb2+ for 3 h, respectively. The maximum adsorption capacity of 87.62 mg/g was obtained at pH of 6.8 and 25 °C. The adsorption isotherms were fitted well by Langmuir model, while both the Elovich and pseudo-second-order kinetic models were possible to fit the adsorption kinetics at different initial concentrations of Pb2+. The adsorption mechanism of Pb2+ on CFO-BFO nanocomposites was mainly to the chemical force and minor to the electrostatic force. [Display omitted]