Bio


Jörgen has a PhD in chemical physics. His educational background is as a graduated engineer in technical physics, which he received at Karlstad University, Sweden, before he did his PhD, at Stockholm University, Sweden. After the PhD he worked for ~2 years in Anders Nilsson's research group at Stockholm University, before he came to Stanford and joined Tony F. Heinz's research group. His research has been around heterogeneous catalysis on metal surfaces, which is the subject for the project that he is working on here at Stanford and SLAC.

Professional Education


  • Doctor of Philosophy, Stockholm University (2017)
  • M.Sc., Karlstad University, Graduated Engineer in Technical Physics (2007)

Stanford Advisors


All Publications


  • The state of zinc in methanol synthesis over a Zn/ZnO/Cu(211) model catalyst. Science (New York, N.Y.) Amann, P., Klötzer, B., Degerman, D., Köpfle, N., Götsch, T., Lömker, P., Rameshan, C., Ploner, K., Bikaljevic, D., Wang, H. Y., Soldemo, M., Shipilin, M., Goodwin, C. M., Gladh, J., Halldin Stenlid, J., Börner, M., Schlueter, C., Nilsson, A. 2022; 376 (6593): 603-608

    Abstract

    The active chemical state of zinc (Zn) in a zinc-copper (Zn-Cu) catalyst during carbon dioxide/carbon monoxide (CO2/CO) hydrogenation has been debated to be Zn oxide (ZnO) nanoparticles, metallic Zn, or a Zn-Cu surface alloy. We used x-ray photoelectron spectroscopy at 180 to 500 millibar to probe the nature of Zn and reaction intermediates during CO2/CO hydrogenation over Zn/ZnO/Cu(211), where the temperature is sufficiently high for the reaction to rapidly turn over, thus creating an almost adsorbate-free surface. Tuning of the grazing incidence angle makes it possible to achieve either surface or bulk sensitivity. Hydrogenation of CO2 gives preference to ZnO in the form of clusters or nanoparticles, whereas in pure CO a surface Zn-Cu alloy becomes more prominent. The results reveal a specific role of CO in the formation of the Zn-Cu surface alloy as an active phase that facilitates efficient CO2 methanol synthesis.

    View details for DOI 10.1126/science.abj7747

    View details for PubMedID 35511988

  • Ultrafast Adsorbate Excitation Probed with Subpicosecond-Resolution X-Ray Absorption Spectroscopy. Physical review letters Diesen, E., Wang, H. Y., Schreck, S., Weston, M., Ogasawara, H., LaRue, J., Perakis, F., Dell'Angela, M., Capotondi, F., Giannessi, L., Pedersoli, E., Naumenko, D., Nikolov, I., Raimondi, L., Spezzani, C., Beye, M., Cavalca, F., Liu, B., Gladh, J., Koroidov, S., Miedema, P. S., Costantini, R., Heinz, T. F., Abild-Pedersen, F., Voss, J., Luntz, A. C., Nilsson, A. 2021; 127 (1): 016802

    Abstract

    We use a pump-probe scheme to measure the time evolution of the C K-edge x-ray absorption spectrum from CO/Ru(0001) after excitation by an ultrashort high-intensity optical laser pulse. Because of the short duration of the x-ray probe pulse and precise control of the pulse delay, the excitation-induced dynamics during the first picosecond after the pump can be resolved with unprecedented time resolution. By comparing with density functional theory spectrum calculations, we find high excitation of the internal stretch and frustrated rotation modes occurring within 200 fs of laser excitation, as well as thermalization of the system in the picosecond regime. The ∼100  fs initial excitation of these CO vibrational modes is not readily rationalized by traditional theories of nonadiabatic coupling of adsorbates to metal surfaces, e.g., electronic frictions based on first order electron-phonon coupling or transient population of adsorbate resonances. We suggest that coupling of the adsorbate to nonthermalized electron-hole pairs is responsible for the ultrafast initial excitation of the modes.

    View details for DOI 10.1103/PhysRevLett.127.016802

    View details for PubMedID 34270277

  • Time-resolved observation of transient precursor state of CO on Ru(0001) using carbon K-edge spectroscopy. Physical chemistry chemical physics : PCCP Wang, H. Y., Schreck, S., Weston, M., Liu, C., Ogasawara, H., LaRue, J., Perakis, F., Dell'Angela, M., Capotondi, F., Giannessi, L., Pedersoli, E., Naumenko, D., Nikolov, I., Raimondi, L., Spezzani, C., Beye, M., Cavalca, F., Liu, B., Gladh, J., Koroidov, S., Miedema, P. S., Costantini, R., Pettersson, L. G., Nilsson, A. 2019

    Abstract

    The transient dynamics of carbon monoxide (CO) molecules on a Ru(0001) surface following femtosecond optical laser pump excitation has been studied by monitoring changes in the unoccupied electronic structure using an ultrafast X-ray free-electron laser (FEL) probe. The particular symmetry of perpendicularly chemisorbed CO on the surface is exploited to investigate how the molecular orientation changes with time by varying the polarization of the FEL pulses. The time evolution of spectral features corresponding to the desorption precursor state was well distinguished due to the narrow line-width of the C K-edge in the X-ray absorption (XA) spectrum, illustrating that CO molecules in the precursor state rotated freely and resided on the surface for several picoseconds. Most of the CO molecules trapped in the precursor state ultimately cooled back down to the chemisorbed state, while we estimate that ∼14.5 ± 4.9% of the molecules in the precursor state desorbed into the gas phase. It was also observed that chemisorbed CO molecules diffused over the metal surface from on-top sites toward highly coordinated sites. In addition, a new "vibrationally hot precursor" state was identified in the polarization-dependent XA spectra.

    View details for DOI 10.1039/c9cp03677f

    View details for PubMedID 31531435

  • Indication of non-thermal contribution to visible femtosecond laser-induced CO oxidation on Ru(0001) JOURNAL OF CHEMICAL PHYSICS Oberg, H., Gladh, J., Marks, K., Ogasawara, H., Nilsson, A., Pettersson, L. G., Ostrom, H. 2015; 143 (7)

    Abstract

    We studied CO oxidation on Ru(0001) induced by 400 nm and 800 nm femtosecond laser pulses where we find a branching ratio between CO oxidation and desorption of 1:9 and 1:31, respectively, showing higher selectivity towards CO oxidation for the shorter wavelength excitation. Activation energies computed with density functional theory show discrepancies with values extracted from the experiments, indicating both a mixture between different adsorbed phases and importance of non-adiabatic effects on the effective barrier for oxidation. We simulated the reactions using kinetic modeling based on the two-temperature model of laser-induced energy transfer in the substrate combined with a friction model for the coupling to adsorbate vibrations. This model gives an overall good agreement with experiment except for the substantial difference in yield ratio between CO oxidation and desorption at 400 nm and 800 nm. However, including also the initial, non-thermal effect of electrons transiently excited into antibonding states of the O-Ru bond yielded good agreement with all experimental results.

    View details for DOI 10.1063/1.4928646

    View details for Web of Science ID 000360440400037

    View details for PubMedID 26298142

  • Detection of adsorbate overlayer structural transitions using sum-frequency generation spectroscopy SURFACE SCIENCE Gladh, J., Oberg, H., Pettersson, L. M., Ostrom, H. 2015; 633: 77–81
  • Probing the transition state region in catalytic CO oxidation on Ru SCIENCE Ostrom, H., Oberg, H., Xin, H., LaRue, J., Beye, M., Dell'Angela, M., Gladh, J., Ng, M. L., Sellberg, J. A., Kaya, S., Mercurio, G., Nordlund, D., Hantschmann, M., HIEKE, F., Kuehn, D., Schlotter, W. F., Dakovski, G. L., Turner, J. J., Minitti, M. P., Mitra, A., Moeller, S. P., Foehlisch, A., Wolf, M., Wurth, W., Persson, M., Norskov, J. K., Abild-Pedersen, F., Ogasawara, H., Pettersson, L. G., Nilsson, A. 2015; 347 (6225): 978-982

    Abstract

    Femtosecond x-ray laser pulses are used to probe the carbon monoxide (CO) oxidation reaction on ruthenium (Ru) initiated by an optical laser pulse. On a time scale of a few hundred femtoseconds, the optical laser pulse excites motions of CO and oxygen (O) on the surface, allowing the reactants to collide, and, with a transient close to a picosecond (ps), new electronic states appear in the O K-edge x-ray absorption spectrum. Density functional theory calculations indicate that these result from changes in the adsorption site and bond formation between CO and O with a distribution of OC-O bond lengths close to the transition state (TS). After 1 ps, 10% of the CO populate the TS region, which is consistent with predictions based on a quantum oscillator model.

    View details for DOI 10.1126/science.1261747

    View details for Web of Science ID 000349958900034

  • Electron- and phonon-coupling in femtosecond laser-induced desorption of CO from Ru(0001) SURFACE SCIENCE Gladh, J., Hansson, T., Ostrom, H. 2013; 615: 65–71
  • Real-time observation of surface bond breaking with an x-ray laser. Science Dell'Angela, M., Anniyev, T., Beye, M., Coffee, R., Föhlisch, A., Gladh, J., Katayama, T., Kaya, S., Krupin, O., LaRue, J., Møgelhøj, A., Nordlund, D., Nørskov, J. K., Oberg, H., Ogasawara, H., Oström, H., Pettersson, L. G., Schlotter, W. F., Sellberg, J. A., Sorgenfrei, F., Turner, J. J., Wolf, M., Wurth, W., Nilsson, A. 2013; 339 (6125): 1302-1305

    Abstract

    We used the Linac Coherent Light Source free-electron x-ray laser to probe the electronic structure of CO molecules as their chemisorption state on Ru(0001) changes upon exciting the substrate by using a femtosecond optical laser pulse. We observed electronic structure changes that are consistent with a weakening of the CO interaction with the substrate but without notable desorption. A large fraction of the molecules (30%) was trapped in a transient precursor state that would precede desorption. We calculated the free energy of the molecule as a function of the desorption reaction coordinate using density functional theory, including van der Waals interactions. Two distinct adsorption wells-chemisorbed and precursor state separated by an entropy barrier-explain the anomalously high prefactors often observed in desorption of molecules from metals.

    View details for DOI 10.1126/science.1231711

    View details for PubMedID 23493709

  • https://doi.org/10.1021/jacs.2c00300 Operando Observation of Oxygenated Intermediates during CO Hydrogenation on Rh Single Crystals Degerman, D., Shipilin, M., Lömker, P., Goodwin, C. M., Gericke, S. M., Hejral, U., Gladh, J., Wang, H., Schlueter, C., Nilsson, A., Amann, P. 2022
  • In Situ Surface-Sensitive Investigation of Multiple Carbon Phases on Fe(110) in the Fischer–Tropsch Synthesis In Situ Surface-Sensitive Investigation of Multiple Carbon Phases on Fe(110) in the Fischer–Tropsch Synthesis Shipilin, M., Degerman, D., Lömker, P., Goodwin, C. M., Rodrigues, G. L., Wagstaffe, M., Gladh, J., Wang, H., Stierle, A., Schlueter, C., Pettersson, L. G., Nilsson, A., Amann, P. 2022; 12: 12

    View details for DOI 10.1021/acscatal.2c00905

  • A high-pressure x-ray photoelectron spectroscopy instrument for studies of industrially relevant catalytic reactions at pressures of several bars The Review of Scientific Instruments Amann, P., Degerman , D., Lee, M., Alexander, J. D., Shipilin, M., Wang, H., Cavalca, F., Weston, M., Gladh, J., Blom, M., Björkhage, M., Löfgren, P., Schlueter, C., Loemker , P., Ederer, K., Drube , W., Noei , H., Zehetner, J., Wentzel, H., Åhlund, J., Nilsson, A., et al 2019; 90: 103102

    View details for DOI 10.1063/1.5109321

  • Catalysis in real time using X-ray lasers CHEMICAL PHYSICS LETTERS Nilsson, A., LaRue, J., Oberg, H., Ogasawara, H., Dell'Angela, M., Beye, M., Ostrom, H., Gladh, J., Norskov, J. K., Wurth, W., Abild-Pedersen, F., Pettersson, L. G. 2017; 675: 145-173
  • Chemical Bond Activation Observed with an X-ray Laser JOURNAL OF PHYSICAL CHEMISTRY LETTERS Beye, M., Oberg, H., Xin, H., Dakovski, G. L., Dell'Angela, M., Foehlisch, A., Gladh, J., Hantschmann, M., Hieke, F., Kaya, S., Kuehn, D., LaRue, J., Mercurio, G., Minitti, M. P., Mitra, A., Moeller, S. P., Ng, M. L., Nilsson, A., Nordlund, D., Norskov, J., Ostrom, H., Ogasawara, H., Persson, M., Schlotter, W. F., Sellberg, J. A., Wolf, M., Abild-Pedersen, F., Pettersson, L. G., Wurth, W. 2016; 7 (18): 3647-3651

    Abstract

    The concept of bonding and antibonding orbitals is fundamental in chemistry. The population of those orbitals and the energetic difference between the two reflect the strength of the bonding interaction. Weakening the bond is expected to reduce this energetic splitting, but the transient character of bond-activation has so far prohibited direct experimental access. Here we apply time-resolved soft X-ray spectroscopy at a free-electron laser to directly observe the decreased bonding-antibonding splitting following bond-activation using an ultrashort optical laser pulse.

    View details for DOI 10.1021/acs.jpclett.6b01543

    View details for Web of Science ID 000383641800019

  • Optical laser-induced CO desorption from Ru(0001) monitored with a free-electron X-ray laser: DFT prediction and X-ray confirmation of a precursor state SURFACE SCIENCE Oberg, H., Gladh, J., Dell'Angela, M., Anniyev, T., Beye, M., Coffee, R., Foehlisch, A., Katayama, T., Kaya, S., LaRue, J., Mogelhoj, A., Nordlund, D., Ogasawara, H., Schlotter, W. F., Sellberg, J. A., Sorgenfrei, F., Turner, J. J., Wolf, M., Wurth, W., Ostrom, H., Nilsson, A., Norskov, J. K., Pettersson, L. G. 2015; 640: 80-88
  • Strong Influence of Coadsorbate Interaction on CO Desorption Dynamics on Ru(0001) Probed by Ultrafast X-Ray Spectroscopy and Ab Initio Simulations PHYSICAL REVIEW LETTERS Xin, H., LaRue, J., Oberg, H., Beye, M., Dell'Angela, M., Turner, J. J., Gladh, J., Ng, M. L., Sellberg, J. A., Kaya, S., Mercurio, G., HIEKE, F., Nordlund, D., Schlotter, W. F., Dakovski, G. L., Minitti, M. P., Foehlisch, A., Wolf, M., Wurth, W., Ogasawara, H., Norskov, J. K., Ostrom, H., Pettersson, L. G., Nilsson, A., Abild-Pedersen, E. 2015; 114 (15)

    Abstract

    We show that coadsorbed oxygen atoms have a dramatic influence on the CO desorption dynamics from Ru(0001). In contrast to the precursor-mediated desorption mechanism on Ru(0001), the presence of surface oxygen modifies the electronic structure of Ru atoms such that CO desorption occurs predominantly via the direct pathway. This phenomenon is directly observed in an ultrafast pump-probe experiment using a soft x-ray free-electron laser to monitor the dynamic evolution of the valence electronic structure of the surface species. This is supported with the potential of mean force along the CO desorption path obtained from density-functional theory calculations. Charge density distribution and frozen-orbital analysis suggest that the oxygen-induced reduction of the Pauli repulsion, and consequent increase of the dative interaction between the CO 5σ and the charged Ru atom, is the electronic origin of the distinct desorption dynamics. Ab initio molecular dynamics simulations of CO desorption from Ru(0001) and oxygen-coadsorbed Ru(0001) provide further insights into the surface bond-breaking process.

    View details for DOI 10.1103/PhysRevLett.114.156101

    View details for Web of Science ID 000352990700006

    View details for PubMedID 25933322

  • Vacuum space charge effects in sub-picosecond soft X-ray photoemission on a molecular adsorbate layer STRUCTURAL DYNAMICS Dell'Angela, M., Anniyev, T., Beye, M., Coffee, R., Foehlisch, A., Gladh, J., Kaya, S., Katayama, T., Krupin, O., Nilsson, A., Nordlund, D., Schlotter, W. F., Sellberg, J. A., Sorgenfrei, F., Turner, J. J., Ostrom, H., Ogasawara, H., Wolf, M., Wurth, W. 2015; 2 (2)

    Abstract

    Vacuum space charge induced kinetic energy shifts of O 1s and Ru 3d core levels in femtosecond soft X-ray photoemission spectra (PES) have been studied at a free electron laser (FEL) for an oxygen layer on Ru(0001). We fully reproduced the measurements by simulating the in-vacuum expansion of the photoelectrons and demonstrate the space charge contribution of the high-order harmonics in the FEL beam. Employing the same analysis for 400 nm pump-X-ray probe PES, we can disentangle the delay dependent Ru 3d energy shifts into effects induced by space charge and by lattice heating from the femtosecond pump pulse.

    View details for DOI 10.1063/1.4914892

    View details for Web of Science ID 000354994100009

    View details for PubMedID 26798795

    View details for PubMedCentralID PMC4711610

  • Unique water-water coordination tailored by a metal surface JOURNAL OF CHEMICAL PHYSICS Schiros, T., Andersson, K. J., MacNaughton, J., Gladh, J., Matsuda, A., Ostrom, H., Takahashi, O., Pettersson, L. G., Nilsson, A., Ogasawara, H. 2013; 138 (23)

    Abstract

    At low coverage of water on Cu(110), substrate-mediated electrostatics lead to zigzagging chains along [001] as observed with STM [T. Yamada, S. Tamamori, H. Okuyama, and T. Aruga, "Anisotropic water chain growth on Cu(110) observed with scanning tunneling microscopy" Phys. Rev. Lett. 96, 036105 (2006)]. Using x-ray absorption spectroscopy we find an anomalous low-energy resonance at ~533.1 eV which, based on density functional theory spectrum simulations, we assign to an unexpected configuration of water units whose uncoordinated O-H bonds directly face those of their neighbors; this interaction repeats over trough sites with enhanced electron density and is analogous to the case of a hydrated electron.

    View details for DOI 10.1063/1.4809680

    View details for Web of Science ID 000321012400033

    View details for PubMedID 23802977

  • Selective Ultrafast Probing of Transient Hot Chemisorbed and Precursor States of CO on Ru(0001) PHYSICAL REVIEW LETTERS Beye, M., Anniyev, T., Coffee, R., Dell'Angela, M., Foehlisch, A., Gladh, J., Katayama, T., Kaya, S., Krupin, O., Mogelhoj, A., Nilsson, A., Nordlund, D., Norskov, J. K., Oberg, H., Ogasawara, H., Pettersson, L. G., Schlotter, W. F., Sellberg, J. A., Sorgenfrei, F., Turner, J. J., Wolf, M., Wurth, W., Ostrom, H. 2013; 110 (18)

    Abstract

    We have studied the femtosecond dynamics following optical laser excitation of CO adsorbed on a Ru surface by monitoring changes in the occupied and unoccupied electronic structure using ultrafast soft x-ray absorption and emission. We recently reported [M. Dell'Angela et al. Science 339, 1302 (2013)] a phonon-mediated transition into a weakly adsorbed precursor state occurring on a time scale of >2 ps prior to desorption. Here we focus on processes within the first picosecond after laser excitation and show that the metal-adsorbate coordination is initially increased due to hot-electron-driven vibrational excitations. This process is faster than, but occurs in parallel with, the transition into the precursor state. With resonant x-ray emission spectroscopy, we probe each of these states selectively and determine the respective transient populations depending on optical laser fluence. Ab initio molecular dynamics simulations of CO adsorbed on Ru(0001) were performed at 1500 and 3000 K providing insight into the desorption process.

    View details for DOI 10.1103/PhysRevLett.110.186101

    View details for Web of Science ID 000319019300011

    View details for PubMedID 23683223

  • Ultrafast soft X-ray emission spectroscopy of surface adsorbates using an X-ray free electron laser JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA Katayama, T., Anniyev, T., Beye, M., Coffee, R., Dell'Angela, M., Foehlisch, A., Gladh, J., Kaya, S., Krupin, O., Nilsson, A., Nordlund, D., Schlotter, W. F., Sellberg, J. A., Sorgenfrei, F., Turner, J. J., Wurth, W., Ostrom, H., Ogasawara, H. 2013; 187: 9-14
  • Adsorption and Cyclotrimerization Kinetics of C2H2 at a Cu(110) Surface JOURNAL OF PHYSICAL CHEMISTRY C Oberg, H., Nestsiarenka, Y., Matsuda, A., Gladh, J., Hansson, T., Pettersson, L. M., Ostrom, H. 2012; 116 (17): 9550–60

    View details for DOI 10.1021/jp300514f

    View details for Web of Science ID 000303426500053

  • X-ray emission spectroscopy and density functional study of CO/Fe(100) JOURNAL OF CHEMICAL PHYSICS Gladh, J., Oberg, H., Li, J., Ljungberg, M. P., Matsuda, A., Ogasawara, H., Nilsson, A., Pettersson, L. G., Ostrom, H. 2012; 136 (3)

    Abstract

    We report x-ray emission and absorption spectroscopy studies of the electronic structure of the predissociative α(3) phase of CO bound at hollow sites of Fe(100) as well as of the on-top bound species in the high-coverage α(1) phase. The analysis is supported by density functional calculations of structures and spectra. The bonding of "lying down" CO in the hollow site is well described in terms of π to π∗ charge transfer made possible through bonding interaction also at the oxygen in the minority spin-channel. The on-top CO in the mixed, high-coverage α(1) phase is found to be tilted due to adsorbate-adsorbate interaction, but still with bonding mainly characteristic of "vertical" on-top adsorbed CO similar to other transition-metal surfaces.

    View details for DOI 10.1063/1.3675834

    View details for Web of Science ID 000299387700038

    View details for PubMedID 22280772