Paper AS-ThM5
Characterization of Nano-objects with Nanoprojectile-Secondary Ion Mass Spectrometry

Thursday, November 1, 2012, 9:20 am, Room 20

The uniqueness of nano-objects due to functionalities not present in bulk size is well documented. Yet methods for molecular characterizations of isolated entities below micrometer dimensions are lacking. One reason is the minute amount of sample for analysis; another is that the characteristics of analytical signals from objects of nanoscale dimensions can be affected by their size, shape and environment. Our approach for the characterization of nano-objects is based on the method of event-by-event bombardment-detection. Bombardment is with a sequence of individual nanoprojectiles, specifically Au₄₀₀⁴⁺ accelerated to velocities of up to 30 km/s. The impacts cause abundant secondary ion emission. We will report on the modulation of the ejecta as a function of the nano-objects’ size, shape and environment and describe the critical parameters for the accurate assay of their surface and core compositions.