Abstract
AbstractRich electron-matter interactions fundamentally enable electron probe studies of materials such as scanning transmission electron microscopy (STEM). Inelastic interactions often result in structural modifications of the material, ultimately limiting the quality of electron probe measurements. However, atomistic mechanisms of inelastic-scattering-driven transformations are difficult to characterize. Here, we report direct visualization of radiolysis-driven restructuring of rutile TiO2 under electron beam irradiation. Using annular dark field imaging and electron energy-loss spectroscopy signals, STEM probes revealed the progressive filling of atomically sharp nanometer-wide cracks with striking atomic resolution detail. STEM probes of varying beam energy and precisely controlled electron dose were found to constructively restructure rutile TiO2 according to a quantified radiolytic mechanism. Based on direct experimental observation, a “two-step rolling” model of mobile octahedral building blocks enabling radiolysis-driven atomic migration is introduced. Such controlled electron beam-induced radiolytic restructuring can be used to engineer novel nanostructures atom-by-atom.
Funder
National Science Foundation
DOE | Advanced Research Projects Agency - Energy
Publisher
Springer Science and Business Media LLC
Subject
General Physics and Astronomy,General Biochemistry, Genetics and Molecular Biology,General Chemistry,Multidisciplinary
Reference42 articles.
1. Reimer, L. & Kohl, H. Transmission Electron Microscopy: Physics of Image Formation. 5th edn, (Springer, Berlin, 2008).
2. Hobbs, L. W. Introduction to analytical electron microscopy, edited by Hren J. J., Goldstein J. I., and Joy D. C. (Scanning Microscopy International, Chicago, 1979), 437.
3. Ugurlu, O. et al. Radiolysis to knock-on damage transition in zeolites under electron beam irradiation. Phys. Rev. B 83, 113408 (2011).
4. Medlin, D. L., Thomas, L. E. & Howitt, D. G. Decomposition of Refractory Carbides in the Analytical Electron-Microscope. Ultramicroscopy 29, 228–232 (1989).
5. Mkhoyan, K. A. & Silcox, J. Electron-beam-induced damage in wurtzite InN. Appl. Phys. Lett. 82, 859–861 (2003).