APPLICATIONS OF X-RAY ABSORPTION SPECTROSCOPY IN NANOSTRUCTURED MATERIALS

Abstract

X-ray absorption spectroscopy has emerged as a powerful characterization technique for investigating the structural, electronic, and chemical properties of nanostructured materials at the atomic scale. This research examines the diverse applications of XAS techniques including X-ray Absorption Near Edge Structure and Extended X-ray Absorption Fine Structure in characterizing nanomaterials across catalysis, energy storage, environmental remediation, and biomedical applications. We conducted comprehensive XAS measurements on 342 nanostructured samples encompassing metal nanoparticles, quantum dots, nanocomposites, and two-dimensional materials using synchrotron radiation facilities. The analysis reveals that XAS provides unique insights into local atomic coordination, oxidation states, and electronic structure that complement conventional characterization methods. For catalytic nanoparticles, in-situ XAS measurements during reaction conditions identified active site transformations and surface reconstruction mechanisms governing catalytic activity. Energy storage nanomaterials showed oxidation state evolution and structural changes during charge-discharge cycles invisible to bulk techniques. Environmental nanoadsorbents revealed contaminant binding mechanisms at molecular level through coordination chemistry analysis. Quantitative EXAFS fitting determined bond lengths with 0.02Å precision and coordination numbers with 10% accuracy, while XANES fingerprinting identified chemical species at concentrations below 1%. The element-specific and chemical-state-sensitive nature of XAS proved particularly valuable for complex nanocomposites where multiple elements coexist in different chemical environments. These findings demonstrate XAS as an indispensable tool for advancing fundamental understanding and rational design of functional nanomaterials across diverse technological applications.