Skip to main content
Hoydoo You

Hoydoo You

Senior Physicist



  • Ph.D. in Physics, 1985 University of Washington
  • BS in Physics Education, 1977 Seoul National University

Professional Experience

  • 1988-1993: Assistant Physicist, Argonne National Laboratory, Materials Science Division, Synchrotron Radiation Studies group.
  • 1985-1988: Assistant Physicist and postdoc: Brookhaven National Laboratory, Physics Department, X-ray scattering studies.

Selected Professional Activities

  • Chair, Proposal Review Panel – Condensed Matter Physics (members: A. Goldman, R. McCurry), Advanced Photon Source, Argonne National Laboratory, 20112013.
  • International Advisory Committee, The 11th International Conference on Surface X-Ray and Neutron Scattering”, Evanston, IL, July 14 - 17, 2010.
  • Advisory Committee (with other members P. Fenter, T.C. Chiang, J. Freeland, D. Fong), X-ray Interface Science at Advanced Photon Source: New Sector Development”, Organized by H. Hong, Jan. 10-11, 2012, Advanced Photon Source, Argonne, IL.
  • Committee on NSF site visit review of Cornell High Energy Synchrotron Source (CHESS), Chair:Y. Petroff, NSF Coordinators: G. Tessema and C. Bouldin, Ithaca, New York, Nov. 1-2, 2010.

Research Interests

  • Research interests are i) the utilization of x-ray techniques for the interfaces of real and model catalysts and ii) the development of the x-ray techniques sensitive to subtle changes occurring at the interfaces. The scope of research activities centers on molecular-level fundamental study of material interfaces important to energy conversion and storage and to heterogeneous gas-phase catalysis, photocatalysis and electrocatalysis. The Approaches involve utilizations of advanced synchrotron x-ray techniques enabling in situ studies of molecules of light elements interacting with solid surfaces under realistic catalytic environments. The necessarily related research interest is developments of advanced x-ray techniques suitable for in situ investigations of such interfaces.

Recent Invited Talks

  • Coherent X-ray Surface Scattering Studies for Imaging and Dynamics of Interfaces, H. You in Workshop for Applications of Ptychography”, Stanford Synchrotron Radiation Laboratory / Linear Coherent Light Source (SSRL / LCLS) Annual Users’ Meeting, Oct. 7-10, 2015
  • Coherent X-ray Surface Scattering Studies for Imaging and Dynamics of Interfaces, H. You, in Workshop Ultra-high Resolution X-ray Imaging for the Energy Sciences at the COSMIC Beamline”, Advanced Light Source (ALS) User Meeting, Oct. 5-7, 2015
  • Coherent Diffraction from Surfaces, Hoydoo You, Workshop on New Science Opportunities Provided by a Multi-bend Achromat Lattice at the APS, Advanced Photon Source, Argonne National Laboratory, October 21 & 22, 2013
  • In situ Synchrotron X-Ray Studies of LSM, LSC, and LSCF Thin Film SOFC Cathodes Grown by Pulse Laser Deposition”, H. You, Symposium I, Functional Materials for Solid Oxide Fuel Cells”, Materials Research Society Fall Meeting, Boston, Nov. 26-30, 2012.
  • Polarization-dependent resonance x-ray scattering”, H. You in Workshop on X-ray Interface Science for the APS upgrade science case committee for X-ray Interface Scattering”, Argonne National Lab, January 10-11, 2012.
  • In situ x-ray scattering studies from interfaces of solid and supercritical CO2 and water”, H. You, Work-shop on Supercritical Carbon Dioxide and Material Interactions, March 21-23, 2011, at Brookhaven National Laboratory.
  • Surface Dynamics Measurements with Coherent Surface X-ray Scattering”, H. You, V. Komanicky, M. Pierce, The annual meeting of the 62nd Annual Meeting of the International Society of Electrochemistry, Symposium 13: Kinetics and Mechanisms of Electrode Reactions: Studies by Spectroscopy, Theory, and New Advanced Methods, Niigata, Japan, September 11, 2011.
  • Structure and reactivity of 1d and 2d model platinum nanoparticle catalysis, Hoydoo You, Daniel Hennessy, Vladimir Komanicky, Michael S. Pierce, Andi Barbour, Kee-Chul Chang, International Conference on Electrified Interfaces, Geneva, New York, June 20-25, 2010.
  • Shape-dependent Activity of Platinum Array Catalyst, H. You, Symposium 4, Electrocatalysis, the 60th annual meeting of International Society of Electrochemistry, Beijing, China, August 16-21, 2009

Recent Publications

  • W. Cha, Y. Liu, H. You, G. B. Stephenson, and A. Ulvestad, Dealloying in Individual Nanoparticles and Thin Film Grains: A Bragg Coherent Diffractive Imaging Study, Advanced Functional Material, 2017, in press.
  • Y. Liu, P. P. Lopes, W. Cha, R. Harder, J. Maser, E. Maxey, M. J. Highland, N. M. Markovic, S. O. Hruszkewycz, G. B. Stephenson, H. You, and A. Ulvestad, Stability Limits and Defect Dynamics in Ag Nanoparticles Probed by Bragg Coherent Diffractive Imaging, Nano Letters, 17, 1595-1601(2017). http://​pubs​.acs​.org/​d​o​i​/​a​b​s​/​10​.​1021​/​a​c​s​.​n​a​n​o​l​e​t​t​.​6​b​04760
  • A. Ulvestad, M. J. Welland, W. Cha, Y. Liu, J.W. Kim, R. Harder, E. Maxey, J. N. Clark, M. J. Highland, H. You, P. Zapol, S. O. Hruszkewycz and G. B. Stephenson, Three-dimensional imaging of dislocation dynamics during the hydriding phase transformation, Nature Material, 16565571 (2017).  http://​www​.nature​.com/​n​m​a​t​/​j​o​u​r​n​a​l​/​v​a​o​p​/​n​c​u​r​r​e​n​t​/​a​b​s​/​n​m​a​t​4842​.html.
  • A. Loheac, A. Barbour, V. Komanicky, C. Zhu, J. Collini, A. Ruffino, Y. Liu, H. You, and M.S. Pierce, Interaction of Molecular Oxygen with Hexagonally Reconstructed Au (001) Surface, J. of Phys. Chem. C, 120, 23001 (2016).
  • J.-H. Kim, G. Kwon, H. Lim, C. Zhu, H. You, Y.-T. Kim, Effects of transition metal doping in Pt/M-TiO2 (M = V, Cr, and Nb) on oxygen reduction reaction activity, J. Power Sources, 320, 188 (2016); corrigendum, ibid 338, 163 (2016).
  • Y. Liu, A. Barbour, V. Komanicky, H. You, X‑ray Crystal Truncation Rod Studies of Surface Oxidation and Reduction on Pt(111). Journal of Physical Chemistry C 120, 16174 (2016).
  • A. Barbour, A. Alatas, Y. Liu, C. Zhu, B.M. Leu, X. Zhang, A. Sandy, M.S. Pierce, X. Wang, S.W. Cheong, H. You, Partial glass isosymmetry transition in multiferroic hexagonal ErMnO3, Physical Review B, 93 (2016) 054113.
  • C. Zhu, R. Harder, A. Diaz, V. Komanicky, A. Barbour, R. Xu, X. Huang, Y. Liu, M.S. Pierce, A. Menzel, H. You, Ptychographic x-ray imaging of surfaces on crystal truncation rod, Applied Physics Letters, 106 (2015) 101604.
  • E.M. Hopper, E. Perret, B.J. Ingram, H. You, K.-C. Chang, P.M. Baldo, P.H. Fuoss, J.A. Eastman, Oxygen Exchange in La0.6Sr0.4Co0.2Fe0.8O3-delta Thin-Film Heterostructures under Applied Electric Potential, Journal of Physical Chemistry C, 119 (2015) 19915-19921.
  • R.M. Karl, A. Barbour, V. Komanicky, C. Zhu, A. Sandy, M.S. Pierce, H. You, Charge-induced equilibrium dynamics and structure at the Ag(001)-electrolyte interface, Physical Chemistry Chemical Physics, 17 (2015) 16682-16687.
  • V. Komanicky, A. Barbour, M. Lackova, M. Zorko, C. Zhu, M. Pierce, H. You, Growth of arrays of oriented epitaxial platinum nanoparticles with controlled size and shape by natural colloidal lithography, Nanoscale Research Letters, 9 (2014) 336.
  • G. Pristas, S. Gabani, E. Gazo, V. Komanicky, M. Orendac, H. You, Influence of hydrostatic pressure on superconducting properties of niobium thin film, Thin Solid Films, 556 (2014) 470-474.
  • P. Fuoss, K.-C. Chang, H. You, In situ X-ray studies of film cathodes for solid oxide fuel cells, Journal of Electron Spectroscopy and Related Phenomena, 190 (2013) 75-83.
  • V. Komanicky, D.C. Hennessy, H. Iddir, P. Zapol, H. You, Electrocatalytic activity of surface oxides on platinum nanofacets and surfaces, Electrochimica Acta, 109 (2013) 440-446.
  • D. Hennessy, V. Komanicky, H. Iddir, M.S. Pierce, A. Menzel, K.-C. Chang, A. Barbour, P. Zapol, H. You, Epitaxial oxide bilayer on Pt (001) nanofacets, Journal of Chemical Physics, 136 (2012) 044704.
  • B.J. Ingram, J.A. Eastman, K.C. Chang, S.K. Kim, T.T. Fister, E. Perret, H. You, P.M. Baldo, P.H. Fuoss, In situ x-ray studies of oxygen surface exchange behavior in thin film La0.6Sr0.4Co0.2Fe0.8O3-delta, Applied Physics Letters, 101 (2012) 051603.
  • M.S. Pierce, A. Barbour, V. Komanicky, D. Hennessy, H. You, Coherent x-ray scattering experiments of Pt(001) surface dynamics near a roughening transition, Physical Review B, 86 (2012) 184108.
  • M.S. Pierce, V. Komanicky, A. Barbour, D.C. Hennessy, C. Zhu, A. Sandy, H. You, Dynamics of the Au (001) surface in electrolytes: In situ coherent x-ray scattering, Physical Review B, 86 (2012) 085410.
  • H. You, M. Pierce, V. Komanicky, A. Barbour, C. Zhu, Study of electrode surface dynamics using coherent surface X-ray scattering, Electrochimica Acta, 82 (2012) 570-575.
  • M.S. Pierce, D.C. Hennessy, K.C. Chang, V. Komanicky, J. Strzalka, A. Sandy, A. Barbour, H. You, Persistent oscillations of x-ray speckles: Pt (001) step flow, Applied Physics Letters, 99 (2011) 121910.
  • D. Strmcnik, D.F. van der Vliet, K.C. Chang, V. Komanicky, K. Kodama, H. You, V.R. Stamenkovic, N.M. Markovic, Effects of Li+, K+, and Ba2+ Cations on the ORR at Model and High Surface Area Pt and Au Surfaces in Alkaline Solutions, Journal of Physical Chemistry Letters, 2 (2011) 2733-2736.
  • V. Komanicky, H. Iddir, K.-C. Chang, A. Menzel, G. Karapetrov, D.C. Hennessy, P. Zapol, H. You, Fabrication and characterization of platinum nanoparticle arrays of controlled size, shape and orientation, Electrochimica Acta, 55 (2010) 7934-7938.
  • M.S. Pierce, K.C. Chang, D. Hennessy, V. Komanicky, M. Sprung, A. Sandy, H. You, Surface X-Ray Speckles: Coherent Surface Diffraction from Au(001), Physical Review Letters, 103 (2009) 165501.
  • C.A. Lucas, P. Thompson, M. Cormack, A. Brownrigg, B. Fowler, D. Strmcnik, V. Stamenkovic, J. Greeley, A. Menzel, H. You, N.M. Markovic, Temperature-Induced Ordering of Metal/Adsorbate Structures at Electrochemical Interfaces, Journal of the American Chemical Society, 131 (2009) 7654-7661.
  • V. Komanicky, H. Iddir, K.-C. Chang, A. Menzel, G. Karapetrov, D. Hennessy, P. Zapol, H. You, Shape-Dependent Activity of Platinum Array Catalyst, Journal of the American Chemical Society, 131 (2009) 5732.
  • C. Wang, D. van der Vilet, K.-C. Chang, H. You, D. Strmcnik, J.A. Schlueter, N.M. Markovic, V.R. Stamenkovic, Monodisperse Pt3Co Nanoparticles as a Catalyst for the Oxygen Reduction Reaction: Size-Dependent Activity, Journal of Physical Chemistry C, 113 (2009) 19365-19368.