1 Scope
This Technical Report provides an introduction to (and some examples of) the types
of information that can be obtained about nanostructured materials using surface-analysis
tools (Section 4). Of equal importance, both general issues or challenges associated with characterizing
nanostructured materials and the specific opportunities or challenges associated with
individual methods are identified (Section 5). As the size of objects or components of materials approaches a few nanometres,
the distinctions among “bulk”, “surface” and “particle” analysis blur. Although some
general issues relevant to characterization of nanostructured materials are identified,
this Technical Report focuses on issues specifically relevant to surface chemical
analysis of nanostructured materials. A variety of analytical and characterization
methods will be mentioned, but this report focuses on methods that are in the domain
of ISO/TC 201 including Auger Electron Spectroscopy, X-ray photoelectron spectroscopy,
secondary ion mass spectrometry, and scanning probe microscopy. Some types of measurements
of nanoparticle surface properties such as surface potential that are often made in
a solution are not discussed in this Report.
Although they have many similar aspects, characterization of nanometre-thick films
or a uniform collection of nanometre-sized particles present different characterization
challenges. Examples of methods applicable to both thin films and to particles or
nano-sized objects are presented. Properties that can be determined include: the presence
of contamination, the thickness of coatings, and the chemical nature of the surface
before and after processing. In addition to identifying the types of information that
can be obtained, the Technical Report summarizes general and technique-specific Issues
that must be considered before or during analysis. These include: identification of
needed information, stability and probe effects, environmental effects, specimen-handling
issues, and data interpretation.
Surface characterization is an important subset of several analysis needs for nanostructured
materials. The broader characterization needs for nanomaterials are within the scope
of ISO/TC 229 and this report has been coordinated with experts of TC 229 Joint Working
Group (JWG) 3.
This introduction to information available about nanomaterials using a specific set
of surface-analysis methods cannot by its very nature be fully complete. However,
important opportunities, concepts and issues have been identified and many references
provided to allow the topics to be examined in greater depth as required.