Conventional surface analysis techniques including XPS, SAM and
ATR-FTIR provide an average surface chemistry over the area of analysis.
Conventional XPS imaging provides chemical imaging with a spatial
resolution of up to 5 μm which is too poor to highlight the different domains
in most heterogeneous surface chemistry and is time consuming.
ToF-SIMS is able to produce maps representing the elemental distribution
across a mineral surface fromthe top most one or two monolayers,
but it does not provide the same degree of chemical information as XPS
or NEXAFS. Additionally, precipitated, adsorbed, reacted and contaminant
species in the outermost molecular layers produce complex mass
spectra which are difficult if not impossible to interpret in conventional
ways [12]. To understand and evaluate the surface oxidation products
varying from particle to particle on copper–iron sulfides, there is a
need to know the surface chemical information with high lateral
resolution.