Synthesis of bismuth nanoparticle-loaded cobalt ferrite for electrochemical detection of heavy metal ions.

As an efficient modified electrode material for the detection of heavy metal ions, bismuth nanoparticles (BiNPs) were loaded on cobalt ferrite (CoFe 2 O 4 ), a unique magnetic photocatalytic material, to fabricate a highly sensitive sensor. The obtained BiNPs@CoFe 2 O 4 nanocomposites showed excellent adsorption and electrical conductivity using a Square Wave Anodic Stripping Voltammetry (SWASV) detection method. Under optimized conditions, the BiNPs@CoFe 2 O 4 /GCE sensor could simultaneously determine Pb 2+ and Cd 2+ , with detection limits of 7.3 and 8.2 nM, respectively. In addition, the BiNPs@CoFe 2 O 4 exhibited acceptable reproducibility and good stability, which indicated great potential for the detection of heavy metal ions in reality.