Monitoring the fate of copper nanoparticles in river biofilms using scanning transmission X-ray microscopy (STXM)

Scanning transmission X-ray microscopy (STXM) at the C 1s and Cu 2p edges was used to study the fate of Cu nanoparticles, including their sorption–dissolution, speciation and distribution in a complex natural river biofilm exposed to 1mgL−1 Cu nanoparticles for 5min, 3days or 7days. The original Cu nanoparticles, ~30nm in diameter, were composed of Cu(I) and Cu(II) species, presumably a Cu(I) core surrounded by oxidized Cu(II). When the Cu …