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Updated: Dec 28, 2025
Energy Dispersive X-ray Tomography for 3D Elemental Mapping of Individual Nanoparticles
Published on: July 5, 2016
Cation Disorder and Local Structural Distortions in AgxBi1-xS2 Nanoparticles
Jagadesh Kopula Kesavan1, Francesco d'Acapito2, Paolo Scardi3
1Department of Physics and Astronomy, University of Bologna, Viale C. Berti Pichat 6/2, 40127 Bologna, Italy.
Abstract:
By combining X-ray absorption fine structure and X-ray diffraction measurements with density functional and molecular dynamics simulations, we study the structure of a set of AgxBi1-xS2 nanoparticles, a materials system of considerable current interest for photovoltaics. An apparent contradiction between the evidence provided by X-ray absorption and diffraction measurements is solved by means of the simulations. We find that disorder in the cation sublattice induces strong local distortions, leading to the appearance of short Ag-S bonds, the overall lattice symmetry remaining close to hexagonal.
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