Characterization of individual ag nanoparticles and their chemical environment.

Silver nanoparticles (NPs) of approximately 5 nm diameter deposited in a single layer on glycine were examined with cluster secondary ion mass spectrometry (SIMS) in the event-by-event bombardment-detection mode. The projectiles used were Au(3)(+), C(60)(+), and Au(400)(4+) with impact energies of 34, 26, and 136 keV, respectively. The highest secondary ion yields were obtained with Au(400)(4+). The method presented can test single or multilayer organization and determine surface coverage. NPs are identified one-by-one for chemical composition. Chemical and physical information in a nonimaging mode was resolved at approximately 10 nm. Grazing vs direct impacts on NPs were identified and quantified. NP fragmentation from direct impacts with Au(400)(4+) and C(60)(+) was observed for the first time.