X-ray absorption spectroscopy for environmental sciences: examples and technical challenges

Due to its element specificity, low detection limit, and independence on long-range and crystalline order, X-ray absorption spectroscopy (XAS) is one of the most versatile tools to elucidate the electronic and molecular structure of almost any element in environmental samples. It is fundamental to study the speciation and structure of dissolved (aqueous) complexes, from the most simple solvated ion to polyatomic complexes, to colloids, amorphous and crystalline solids. Furthermore, it is extremely useful to study sorption and redox reactions at the water/solid interface. I will demonstrate its application in environmental chemistry to study the fate of metal contaminants in soils, sediments and water bodies.