When Crystals Go Nano – The Role of Advanced X‐ray Total Scattering Methods in Nanotechnology

Controlling the stoichiometry, structure, defects, size, and shape of engineered nanomaterials (in the forms of powders, colloids, and thin films) is a fundamental issue in designing new functionalities and providing reproducible and efficient synthetic methods, thus enabling the construction of high‐tech devices. Nanosized materials are complex systems; therefore, to meet these goals, advanced physicochemical methods and dedicated and robust characterization tools, bearing a solid statistical value, are required. Here we present frontier techniques based on X‐ray total scattering (mainly, but not only, synchrotron‐based) and the Debye scattering equation modeling. The method has been developed in the field of crystalline nanomaterials and nanocomposites, from very small colloidal semiconductor quantum dots to halide perovskites, metals, oxides, nanodrugs, and bioceramics, and provides atomic‐ to nanometer‐scale characterization to an unbeatable level. Examples from the recent scientific literature are presented. Nanocrystallography tools, based on wide‐angle total scattering techniques and on the Debye Scattering Equation, enable frontier characterization of structure, size, morphology, and defectiveness of nanopowders and colloids.