Efficient remediation of heavy metal-contaminated water using a magnetically collectible nanoscale Cu/Fe/rGO primary battery

The removal of highly toxic heavy metal ions is essentially the migration of heavy metal ions from water to materials through adsorption, complexation, exchange, and other forms. However, heavy metals still exist as highly toxic ions on the surface of materials, easily desorbed, and cause secondary pollution. In this study, a novel primary battery of graphene-supported zero-valent copper/iron bimetallic composites (Cu/Fe/rGO) was first prepared with copper as the positive electrode, iron as the negative electrode, and graphene as the "wire". The network -like nanoscale primary battery was fabricated for the reduction and removal of typical highly toxic heavy metal ions (Pb2+) from the water environment. The removal rate of Pb2+ within 20 min was 95.28%. The Pb-immobilized Cu/Fe/rGO primary battery after treatment can be easily separated via a weak magnetic field and maintained an excellent removal rate of Pb2+ during 6 cycles of use. The great potential of Cu/Fe/rGO primary battery in Pb2+ reduction removal was due to its high reduction ability, large surface area, and magnetic separability. This study provides an important foundation for the rapid and stable removal of heavy metals from water, which may have a tremendous application prospect in environmental fields.