Removal of cobalt ions from aqueous solution by Ag/Fe bimetallic nanoparticles

Abstract

Ag/Fe bimetallic nanoparticles were synthesized by simple two-step method without nitrogen atmosphere. In the whole reaction process, polyvinyl pyrrolidone protected Fe nanoparticles and Ag/Fe bimetallic nanoparticles from oxidation. Moreover, the nanoparticles were characterized through high-resolution environment scanning electron microscope, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and energy dispersive spectrometer. The Fe nanoparticles and Ag/Fe bimetallic nanoparticles were used to remove Co(II) ions from aqueous solution. Experiments revealed that Ag/Fe bimetallic nanoparticles could quickly remove Co(II) ions from the aqueous solutions within 5 min, and the removal rate was up to 99%. Compared with Fe nanoparticles, as-prepared Ag/Fe bimetallic nanoparticles exhibit a higher adsorption capacity and faster reaction rate due to the numerous nanoscale Ag/Fe primary batteries, which indicates that the Ag/Fe bimetallic nanoparticles are highly promising for the applications of water treatment.

Keywords:

• Ag/Fe bimetallic nanoparticles
• Nanoscale primary batteries
• Remediation
• Cobalt ion

Acknowledgments

This work was supported by the National Nature Science Foundation of China (Project Nos. 21105001 and 21471005), NRF graphene project, National Key Research Institute Project, the Korea Basic Science Institute, and Priority Research Centers Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2014R1A6A1031189).