Probing structures and structural evolution of nanomaterials by X-ray absorption fine structure spectroscopy

X-ray absorption fine structure (XAFS) is a powerful X-ray spectroscopy technique developed to interrogate materials for their structural and chemical properties, and is widely employed in nanomaterials research. This article features an overview on the basic principles and experimental techniques of XAFS, followed by a number of examples in which XAFS help solve problems that are unique to nanoscience and nanotechnology. The example gives a broad coverage on how XAFS infers morphology and atomic motifs of nanomaterials in steady states, using ex situ spectral techniques, as well as how XAFS tracks the structural evolution of nanomaterials during active processes, such as catalysis and nanomaterials growth, using in situ and in operando techniques.