Enhancing the imaging power of microscopy to identify all chemical types of atom, from low- to high-atomic-number elements,would significantly contribute for a direct determinationof material structures. Electron microscopes have successfully provided images of heavy-atom positions, particularly by the annular dark-field method1,2, but detection of light atoms was difficult owing to their weak scattering power. Recent developments of aberration-correction electron optics3,4,5 have significantly advanced the microscope performance, enabling identification of individual light atoms such as oxygen6,7,8,9, nitrogen7,9, carbon9,10,11, boron9 and lithium12,13. However, the lightest hydrogen atom has not yet been observed directly, except in the specific condition of hydrogen adatoms on a graphene membrane14. Here we show the first direct imaging of the hydrogen atom in a crystalline solid YH2, based on a classic ‘hollow-cone’ illumination theory15,16,17,18 combined with state-of-the-art scanning transmission electronmicroscopy. The optimizedhollow-cone condition derived from the aberration-corrected microscope parameters confirms that the information transfer can be extended to 22.5 nm−1, which corresponds to a spatial resolution of about 44.4 pm. These experimental conditions can be readily realized with the annular bright-field imaging in scanning transmission electron microscopy19,20 according to reciprocity21, revealing successfully the hydrogen-atom columns as dark dots, as anticipated from phase contrast of a weak-phase object22.
Subscribe to Journal
Get full journal access for 1 year
only $17.42 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Crewe, A. V., Wall, J. & Langmore, J. Visibility of single atoms. Science 168, 1338–1340 (1970).
Pennycook, S. J. & Boatner, L. A. Chemically sensitive structure-imaging with a scanning transmission electron microscope. Nature 336, 565–567 (1988).
Haider, M. et al. Electron microscopy image enhanced. Nature 392, 768–769 (1998).
Batson, P. E., Dellby, N. & Krivanek, O. L. Sub-ångstrom resolution using aberration corrected electron optics. Nature 418, 617–620 (2002).
Sawada, H. et al. Correction of higher order geometrical aberration by triple 3-fold astigmatism field. J. Electron Microsc. 58, 341–347 (2009).
Jia, C. L. & Urban, K. Atomic-resolution measurement of oxygen concentration in oxide materials. Science 303, 2001–2004 (2004).
Okunishi, E. et al. Visualization of light elements at ultrahigh resolution by STEM annular bright field microscopy. Microsc. Microanal. 15, 164–165 (2009).
Findlay, S. D. et al. Dynamics of annular bright field imaging in scanning transmission electron microscopy. Ultramicroscopy 110, 903–923 (2010).
Krivanek, O. L. et al. Atom-by-atom structural and chemical analysis by annular dark-field electron microscopy. Nature 464, 571–574 (2010).
Liu, Z. et al. Imaging the dynamic behaviour of individual retinal chromophores confined inside carbon nanotubes. Nature Nanotech. 2, 422–425 (2007).
Girit, Ö. Ç. et al. Graphene at the edge: Stability and dynamics. Science 323, 1705–1708 (2009).
Shao-Horn, Y., Croguennec, L., Delmas, C., Nelson, E. C. & O’Keefe, M. A. Atomic resolution of lithium ions in LiCoO2 . Nature Mater. 2, 464–467 (2003).
Oshima, Y. et al. Direct imaging of lithium atoms in LiV2O4 by spherical aberration-corrected electron microscopy. J. Electron Microsc. 59, 457–461 (2010).
Meyer, J. C., Girit, C. O., Crommie, M. F. & Zettl, A. Imaging and dynamics of light atoms and molecules on graphene. Nature 454, 319–322 (2008).
Mathews, W. W. The use of hollow-cone illumination for increasing image contrast in microscopy. Trans. Am. Microsc. Soc. 2, 190–195 (1953).
Hanssen, K. J. & Trepte, L. Die Kontrastübertragung im elektronemikroskop bei partiell kohärentercbeleuchtung (in German). Optik 33, 166–181 (1971).
Rose, H. Nonstandard imaging methods in electron microscopy. Ultramicroscopy 2, 251–267 (1977).
Dinges, C., Kohl, H. & Rose, H. High-resolution imaging of crystalline objects by hollow-cone illumination. Ultrmicroscopy 55, 91–100 (1994).
Rose, H. Phase-contrast in scanning transmission electron microscopy. Optik 39, 416–436 (1974).
Cowley, J. M., Hansen, M. S. & Wang, S-Y. Imaging modes with an annular detector in STEM. Ultramicroscopy 58, 18–24 (1995).
Cowley, J. M. Image contrast in a transmission scanning electron microscope. Appl. Phys. Lett. 15, 58–59 (1969).
Scherzer, O. The theoretical resolution limit of the electron microscope. J. Appl. Phys. 20, 20–29 (1949).
Komoda, T. Electron microscopic observation of crystal lattices on the level with atomic dimension. Jpn. J. Appl. Phys. 5, 603–607 (1966).
Kunath, W., Zemlin, F. & Weiss, K. Apodization in phase-contrast electron microscopy realized with hollow-cone illumination. Ultramicroscopy 16, 123–138 (1985).
O’Keefe, M. A. et al. Sub-ångstrom high-resolution transmission electron microscopy at 300 keV. Ultramicroscopy 89, 215–241 (2001).
Nellist, P. D. et al. Direct sub-ångstrom imaging of a crystal lattice. Science 305, 1741 (2004).
Sawada, H. et al. STEM imaging of 47 pm-separated atomic columns by a spherical aberration-corrected electron microscope with a 300-kV cold field emission gun. J. Electron Microsc. 58, 357–361 (2009).
Egerton, R. F. Electron Energy-Loss Spectroscopy in the Electron Microscope 2nd edn (Plenum, 1996).
Ishizuka, K. A practical approach for STEM image simulation based on the FFT multislice method. Ultramicroscopy 90, 71–83 (2002).
Kabius, B. et al. First application of Cc-corrected imaging for high-resolution and energy-filtered TEM. J. Electron Microsc. 58, 147–155 (2009).
Findlay, S. et al. Direct imaging of hydrogen within a crystalline environment. Appl. Phys. Express 3, 116603 (2010).
R.I. was supported as a Japan Society for the Promotion of Science research fellow. E.A. acknowledges support from a Grant-in-Aid for Scientific Research on Priority Areas ‘Atomic scale modification’ from the Ministry of Education, Culture, Sports, Science and Technology of Japan.
The authors declare no competing financial interests.
About this article
Cite this article
Ishikawa, R., Okunishi, E., Sawada, H. et al. Direct imaging of hydrogen-atom columns in a crystal by annular bright-field electron microscopy. Nature Mater 10, 278–281 (2011). https://doi.org/10.1038/nmat2957
Physical Sciences Reviews (2020)
Atomic Imaging of Subsurface Interstitial Hydrogen and Insights into Surface Reactivity of Palladium Hydrides
Angewandte Chemie International Edition (2020)
Advanced Materials (2020)
Observation of fault-free coherent layer during Ruddlesden–Popper faults generation in LaNiO3 thin films
Journal of the Korean Ceramic Society (2020)