# Single-Shot 3D Diffractive Imaging of Core-Shell Nanoparticles with Elemental Specificity

## TL;DR

This paper demonstrates single-shot 3D imaging of core-shell nanoparticles with elemental specificity using femtosecond x-ray laser pulses, achieving high resolution and precise structural determination.

## Contribution

The study introduces a method for 3D coherent diffractive imaging of nanoparticles with elemental contrast from single shots, utilizing Ewald sphere curvature and symmetry.

## Key findings

- Achieved 6 nm resolution in 3D imaging.
- Determined core and shell sizes with high accuracy.
- Reconstructed elemental distribution inside nanoparticles.

## Abstract

We report 3D coherent diffractive imaging of Au/Pd core-shell nanoparticles with 6 nm resolution on 5-6 femtosecond timescales. We measured single-shot diffraction patterns of core-shell nanoparticles using very intense and short x-ray free electron laser pulses. By taking advantage of the curvature of the Ewald sphere and the symmetry of the nanoparticle, we reconstructed the 3D electron density of 34 core-shell structures from single-shot diffraction patterns. We determined the size of the Au core and the thickness of the Pd shell to be 65.0 +/- 1.0 nm and 4.0 +/- 0.5 nm, respectively, and identified the 3D elemental distribution inside the nanoparticles with an accuracy better than 2%. We anticipate this method can be used for quantitative 3D imaging of symmetrical nanostructures and virus particles.

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Source: https://tomesphere.com/paper/1702.06600