- © 2014 Mineralogical Society of America
Chemistry and physics of mineral surfaces and interfaces are pivotal in understanding the many processes occurring in the extremely diverse domains in which mineral matter is encountered, such as geochemistry of soils and aquifers (Morse and Arvidson 2002), interaction with microbial organisms (Brown et al. 1999), catalysis (Corma 1995) and nanotechnology (Fu and Wagner 2007). The study of mineral surfaces as archetypes of surfaces of insulators mostly started twenty years ago, which is rather recent with respect to the general evolution of surface science. The likely origin of such delay, surprising given the ubiquity of mineral matter, was the difficulty in operating methods dominated by electron probes to deal with insulating substrates and to the deterrent effect of the complex chemical composition of the encountered compounds. In the burgeoning development of the analysis of mineral surfaces, techniques of investigation which belong to the well-stocked toolkit available to surface science currently involve both versatile enough traditional methods and emerging techniques that have proved relevant. Photoelectron spectroscopy, synchrotron-based diffraction and absorption are cornerstones techniques for the analysis of all surfaces, including those of mineral compounds, as well as pure photon probes which are not affected by the insulating nature of substrates, such as infrared spectroscopy, Raman spectroscopy and X-ray diffraction.
In the 1990’s, a strong incentive for the development of analysis of mineral surfaces came from the emergence of atomic force microscopy (AFM) which had the potential ability to probe surfaces of insulators and which is a powerful tool for the study of surface topography and structure at sub-nanometer-scale resolution (Binnig et al. 1986). Extremely flexible, the technique can be used in any condition, either vacuum or gas or liquid phases, and on any substrate. The instrument itself is of small size, commercially available, friendly to use and can be operated at …