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Probing Exfoliated Graphene Layers and Their Lithiation with Microfocused X-rays.

ABSTRACT: X-ray diffraction is measured on individual bilayer and multilayer graphene single-crystals and combined with electrochemically induced lithium intercalation. In-plane Bragg peaks are observed by grazing incidence diffraction. Focusing the incident beam down to an area of about 10 ?m × 10 ?m, individual flakes are probed by specular X-ray reflectivity. By deploying a recursive Parratt algorithm to model the experimental data, we gain access to characteristic crystallographic parameters of the samples. Notably, it is possible to directly extract the bi/multilayer graphene c-axis lattice parameter. The latter is found to increase upon lithiation, which we control using an on-chip peripheral electrochemical cell layout. These experiments demonstrate the feasibility of in situ X-ray diffraction on individual, micron-sized single crystallites of few- and bilayer two-dimensional materials.

SUBMITTER: Zielinski P

PROVIDER: S-EPMC6750871 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Probing Exfoliated Graphene Layers and Their Lithiation with Microfocused X-rays.

Zielinski Patrik P Kühne Matthias M Kärcher Daniel D Paolucci Federico F Wochner Peter P Fecher Sven S Drnec Jakub J Felici Roberto R Smet Jurgen H JH

Nano letters 20190522 6

X-ray diffraction is measured on individual bilayer and multilayer graphene single-crystals and combined with electrochemically induced lithium intercalation. In-plane Bragg peaks are observed by grazing incidence diffraction. Focusing the incident beam down to an area of about 10 μm × 10 μm, individual flakes are probed by specular X-ray reflectivity. By deploying a recursive Parratt algorithm to model the experimental data, we gain access to characteristic crystallographic parameters of the sa ...[more]

PMID: 31095394

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