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Cation Disorder and Local Structural Distortions in AgxBi1-xS2 Nanoparticles.

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.

SUBMITTER: Kopula Kesavan J

PROVIDER: S-EPMC7075158 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Cation Disorder and Local Structural Distortions in AgxBi1-xS2 Nanoparticles.

Kopula Kesavan Jagadesh J d'Acapito Francesco F Scardi Paolo P Stavrinadis Alexandros A Akgul Mehmet Zafer MZ Burgués-Ceballos Ignasi I Konstantatos Gerasimos G Boscherini Federico F

Nanomaterials (Basel, Switzerland) 20200212 2

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 indu ...[more]

PMID: 32059432

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