Silver nanoparticles AgNPs having small (6-8 nm) diameter, were synthesized in water in solutions and left interacting with diluted 3d metals (Co2+ or Ni2+ ions) solution (1-5 ppm range). The interactions between AgNPs and the metallic ions modify the optical response of the nanoparticles demonstrating their ability to capture metallic ions from water and making them valuable as metal contamination sensor.
Here the coordination chemistry of Co and Ni adsorbed onto AgNPs is probed combining X-ray absorption spectroscopy (XAS) and X-ray photoelectron spectroscopy (XPS).