Keynote
INTERROGATING NANOSTRUCTURE WITH ELECTRON BEAMS

This talk will describe the development of methods for locating the position, type and bonding of atoms within nanostructured materials using electron beams. It will illustrate these with applications to functional perovskites, plasmonic nanostructures and semiconducting systems.

Convergent beam electron diffraction patterns are rich with information about the arrangement and bonding of atoms within a specimen [1] and underpin the generation of scanning transmission electron microscope (STEM) images. Furthermore, the converged electron probe can be focused to a cross-over less than an Ångström in diameter, allowing a small number of atoms within the specimen to be isolated and analysed. By interrogating key features in these patterns different types of specimen information can be gleaned and imaged in STEM.

This talk will give an overview of these methods and will describe their application; for example, to mapping surface plasmon polaritons in metallic nanostructures [2]; revealing Li-dependent 3D octahedral superlattices in Li-ion conductors [3]; understanding crystal growth and shape control in metal nanoparticles [4,5]; and revealing domain structures in solar cell perovskites [6].

[1] Nakashima PNH, Moodie AF & Etheridge J PNAS 110 (2013) 14144.

[2] Zhu Y, Nakashima PNH, Funston AF, Bourgeois L, Etheridge J ACS Nano 11 (2017) 11383.

[3] Zhu Y, Withers R, Bourgeois LN, Dwyer C, Etheridge J Nature Materials 14 (2015) 1142.

[4] Katz-Boon H, Walsh M, Dwyer C, Mulvaney P, Funston AF, Etheridge J Nano Letters 15 (2015) 1635

[5] Walsh M, Tong W, Katz-Boon H, Mulvaney P, Etheridge J, Funston AF, Accounts Chemical Research (2017) in press DOI: 10.1021/acs.accounts.7b00313.

[6] Rothmann M, Li W, Zhu Y, Bach U, Spiccia L, Etheridge J, Cheng Y, Nature Communications 8 (2017) 14547.