Preparation of nanoparticle samples for ultrafast electron diffraction

ZHONG, Y.; KESKIN, S.; ROSSOS, A.; CORTHEY, G.; LOCH, R.; ZHANG, D. ; EPP, S. ; MILLER, R. J. D.

Banff, Alberta

Congreso; 4th Banff Meeting on Structural Dynamics; 2015

Nanoparticles exhibit a number of special properties in comparison to bulk material. Particularly in the field of ultrafast sciences, nanoparticles are expected to show characteristic lattice dynamics upon ultrafast laser excitation [1]. These ultrafast lattices dynamics can be directly observe by means of ultrafast X-ray diffraction and ultrafast electron diffraction (UED) [2]. Due to the enhanced cross-section of electron atom scattering, which is times higher than the one for X-rays, a sample with few tens of nanometer to few hundred nanometers is required. A remaining challenge is to prepare nanoparticles samples with such a typical thickness. Furthermore, samples with sufficient area are required, especially for single shot UED devices such as the REGAE facility (Relativistic Electron Gun for Atomic Exploration). Here, we present an easy method to prepare nanoparticle samples suitable for UED, by mixing them with epoxy resins and slicing the cured mixture with a microtome. An alpha-Fe2O3 nanoparticle sample prepared by this method will be shown together with the diffraction pattern obtained in our transmission electron microscope. The relation between nanoparticle concentration and melting of epoxy by electron beam will be discussed. References: [1] Gregory V. Hartland,The Journal of Chemical Physics 116, 8048 (2002). [2] R. J. Dwayne Miller, Science 343, 1108-1116 (2014).