Senior Research Scientist
Chemical Physics and Analysis Group
Senior Research Scientist
Chemical Physics and Analysis Group

Biography

Patrick El-Khoury received a BS in chemistry from the American University of Beirut (2003−2006, advisor: B. R. Kaafarani), a doctorate in photochemical sciences from Bowling Green State University (2006−2010, advisor: A. N. Tarnovsky), and postdoctoral training at the University of California, Irvine (2010−2012, advisor: V. A. Apkarian). Soon after, he joined Pacific Northwest National Laboratory (PNNL) as a Linus Pauling Distinguished Postdoctoral Research fellow (2013−2016, mentor: Wayne P. Hess). Currently, Patrick is a senior research scientist in the Chemical Physics and Analysis group, within the Physical Sciences Division at PNNL. Among other things, he spends his days worrying about molecules, plasmons, and their interactions as gauged through tip-enhanced Raman nanospectroscopy and nanoimaging.

Research Interest

  • Multimodal hyperspectral (non)linear optical nanospectroscopy and nanoimaging: instrument development
  • Ultrasensitive and high spatial resolution chemical and biological detection and imaging
  • Time-integrated and time-resolved photoemission electron microscopy: applications in nanophotonics, all-optical nanocircuitry, and joint nm-fs characterization of low-dimensional materials
  • Electronic and vibrational spectroscopy from ab initio molecular dynamics simulations

Education

  • PhD in Photochemical Sciences, Bowling Green State University, Ohio
  • BS in Chemistry, American University of Beirut, Lebanon

Awards and Recognitions

  • Exceptional Achievement Award, PNNL (2019)
  • Outstanding Performance Awards, PNNL (2017, 2018, 2019)
  • Ronald L. Brodzinski Early Career Exceptional Achievement Award, PNNL (2017)
  • Bringing Excellence to Science & Technology Award, PNNL (2017)
  • Linus Pauling Distinguished Postdoctoral Research Fellowship, PNNL (2013-2016)
  • McMaster Fellowship: Outstanding Academic Fellow, Bowling Green State University (2007)

Publications

2022

  • Obloy LM, PZ El-Khoury, AN Tarnovsky. 2022. “Excited-State-Selective Ultrafast Relaxation Dynamics and Photoisomerization of trans-4,4′-Azopyridine,” The Journal of Physical Chemistry Letters, 13 (46), 10863-10870. doi: 10.1021/acs.jpclett.2c02523
  • Mantilla ABC, CF Wang, Y Gu, ZD Schultz, PZ El-Khoury. 2022. “Multipolar Raman Scattering vs Interfacial Nanochemistry: Case of 4-Mercaptopyridine on Gold,” Journal of the American Chemical Society. 144 (45), 20561-20565. doi: 10.1021/jacs.2c10132             
  • Morales AC, JM Tomlin, CP West, ... PZ El-Khoury et al. 2022. “Atmospheric emission of nanoplastics from sewer pipe repairs,” Nat. Nanotechnol. 17, 1171–1177. doi: 10.1038/s41565-022-01219-9
  • El-Khoury PZ, N Jiang, Z Schultz. 2022. “Nanophotonics for Chemical Imaging and Spectroscopy,” The Journal of Physical Chemistry C, 126 (41), 17471-17473. doi: 10.1021/acs.jpcc.2c06603
  • Wang CF and PZ El-Khoury. 2022. “Resonant Coherent Raman Scattering from WSe2,” The Journal of Physical Chemistry A, 126 (34), 5832-5836. doi: 10.1021/acs.jpca.2c04120
  • Wang CF and PZ El-Khoury. 2022 “Multimodal (Non) Linear Optical Nanoimaging and Nanospectroscopy,” The Journal of Physical Chemistry Letters, 13 (31), 7350-7354. doi: 10.1021/acs.jpclett.2c01993
  • Rodriguez A, A Krayev, M Velický, O Frank, and PZ El-Khoury. 2022. “Nano-optical Visualization of Interlayer Interactions in WSe2/WS2 Heterostructures,” The Journal of Physical Chemistry Letters 13 (25), 5854-5859. doi: 10.1021/acs.jpclett.2c01250
  • O’Callahan BT and PZ El-Khoury. 2022. “A Closer Look at Tip-Enhanced Raman Chemical Reaction Nanoimages,” The Journal of Physical Chemistry Letters, 13 (17), 3886-3889. doi: 10.1021/acs.jpclett.2c00574
  • Crampton KT, AG Joly, and PZ El-Khoury. 2022. “Uncovering surface plasmon optical resonances in nanohole arrays through interferometric photoemission electron microscopy,” Applied Physics Letters, 120 (8), 081102. doi: 10.1063/5.0082481
  • Wang CF, BT O’Callahan, BW Arey, D Kurouski, and PZ El-Khoury. 2022. “High-Resolution Raman Nano-Imaging with an Imperfect Probe,” The Journal of Physical Chemistry C, 126 (8), 4089-4094. doi: 10.1021/acs.jpcc.1c10459
  • Prabhakaran V, J Romo, A Bhattarai, K George, ZM Norberg, D Kalb, … PZ El-Khoury, et al. 2022. ”Integrated photoelectrochemical energy storage cells prepared by benchtop ion soft landing,” Chemical Communications, 58 (65), 9060-9063. doi: 10.1039/D2CC02595G

2021

  • PZ El-Khoury. 2021. “Tip-Enhanced Raman Scattering on Both Sides of the Schrödinger Equation,” Accounts of Chemical Research, 54 (24), 4576-4583. doi: 10.1021/acs.accounts.1c00597
  • Wang CF and PZ El-Khoury. 2021. “Multimodal Tip-Enhanced Nonlinear Optical Nanoimaging of Plasmonic Silver Nanocubes,” The Journal of Physical Chemistry Letters, 12 (44), 10761-10765. doi: 10.1021/acs.accounts.1c00597
  • Gabel M, PZ El-Khoury, and Y Gu. 2021.  “Imaging Charged Exciton Localization in van der Waals WSe2/MoSe2 Heterobilayers,” The Journal of Physical Chemistry Letters, 12 (43), 10589-10594. [doi: 10.1021/acs.jpclett.1c03093             
  • Wang CF, BT O’Callahan, A Krayev, and PZ El-Khoury. 2021. “Nanoindentation-enhanced tip-enhanced Raman spectroscopy,” The Journal of Chemical Physics, 154 (24), 241101. doi: 10.1063/5.0056541
  • Wang CF, M Zamkov, and PZ El-Khoury. 2021. “Ambient Tip-Enhanced Photoluminescence with 5 nm Spatial Resolution,” The Journal of Physical Chemistry C, 125 (22), 12251-12255. doi: 10.1021/acs.jpcc.1c04012
  • Zhao X, S Campbell, PZ El-Khoury, Y Jia, GQ Wallace, A Claing, et al. 2021. “Surface-enhanced raman scattering optophysiology nanofibers for the detection of heavy metals in single breast cancer cells,” ACS Sensors, 6 (4), 1649-1662. doi: 10.1021/acssensors.1c00332
  • Cao X, L Zou, BE Matthews, L Zhang, X He, X Ren, and MH Engelhard, et al. 2021. "Optimization of fluorinated orthoformate based electrolytes for practical high-voltage lithium metal batteries." Energy Storage Materials 34, no. n/a:76-84. PNNL-SA-153014. doi:10.1016/j.ensm.2020.08.035
  • Crampton KT, AG Joly, and PZ El-Khoury. 2021. "Surface plasmon polariton pulse shaping via two-dimensional Bragg grating pairs." Nanophotonics 10, no. 2:959-965. PNNL-SA-156139. doi:10.1515/nanoph-2020-0522
  • Gabel ML, BT O'Callahan, CE Groome, C Wang, R Ragan, Y Gu, and PZ El-Khoury. 2021. "Mapping Molecular Adsorption Configurations with < 5 nm Spatial Resolution through Ambient Tip-Enhanced Raman Imaging." Journal of Physical Chemistry Letters 12, no. 14:3586-3590. PNNL-SA-160827. doi:10.1021/acs.jpclett.1c00661
  • Li Z, PZ El-Khoury, and D Kurouski. 2021. "Tip-Enhanced Raman Imaging of Photocatalytic Reactions on Thermally-Reshaped Gold and Gold-Palladium Microplates." Chemical Communications 57, no. 7:891-894. PNNL-SA-153878. doi:10.1039/D0CC07060B
  • Li Z, J Rigor, N Large, PZ El-Khoury, and D Kurouski. 2021. "Underlying Mechanisms of Hot Carrier-Driven Reactivity on Bimetallic Nanostructures." Journal of Physical Chemistry C 125, no. 4:2492-2501. PNNL-SA-159335. doi:10.1021/acs.jpcc.1c00155
  • Wang C, and PZ El-Khoury. 2021. "Imaging Plasmons with Sub-2 nm Spatial Resolution via Tip-Enhanced Four-Wave Mixing." Journal of Physical Chemistry Letters 12, no. 14:3535-3539. PNNL-SA-159334. doi:10.1021/acs.jpclett.1c00763
  • Wang C, BT O'Callahan, AV Krayev, and PZ El-Khoury. 2021. "Nanoindentation-Enhanced Tip-Enhanced Raman Spectroscopy." The Journal of Chemical Physics 154, no. 24:241101. PNNL-SA-162396. doi:10.1063/5.0056541
  • Wang C, M Zamkov, and PZ El-Khoury. 2021. "Ambient Tip-Enhanced Photoluminescence with 5 nm Spatial Resolution." Journal of Physical Chemistry C 125, no. 22:12251-12255. PNNL-SA-163537. doi:10.1021/acs.jpcc.1c04012
  • Zhao X, S Campbell, PZ El-Khoury, Y Jia, G Wallace, A Claing, and C Bazuin, et al. 2021. "Surface-Enhanced Raman Scattering Optophysiology Nanofibers for the Detection of Heavy Metals in Single Breast Cancer Cells." ACS Sensors 6, no. 4:1649-1662. PNNL-SA-161013. doi:10.1021/acssensors.1c00332

2020

  • Apra E, A Bhattarai, ET Baxter, S Wang, GE Johnson, N Govind, and PZ El-Khoury. 2020. "Simplified Ab Initio Molecular Dynamics-Based Raman Spectral Simulations." Applied Spectroscopy. PNNL-SA-146662. doi:10.1177/0003702820923392
  • Bhattarai A, Z Cheng, AG Joly, IV Novikova, JE Evans, Z Schultz, and MR Jones, et al. 2020. "Tip-Enhanced Raman Nanospectroscopy of Smooth Spherical Gold Nanoparticles." The Journal of Physical Chemistry Letters 11, no. 5:1795-1801. PNNL-SA-150682. doi:10.1021/acs.jpclett.0c00217
  • Bhattarai A, KT Crampton, AG Joly, C Wang, Z Schultz, and PZ El-Khoury. 2020. "A Closer Look at Corrugated Au Tips." The Journal of Physical Chemistry Letters 11, no. 5:1915. PNNL-SA-150954. doi:10.1021/acs.jpclett.0c00305
  • Bhattarai A, BT O'Callahan, C Wang, S Wang, and PZ El-Khoury. 2020. "Spatio-Spectral Characterization of Multipolar Plasmonic Modes of Au Nanorods via Tip-Enhanced Raman Scattering." Journal of Physical Chemistry Letters 11, no. 8:2870-2874. PNNL-SA-151304. doi:10.1021/acs.jpclett.0c00485
  • Crampton KT, AG Joly, and PZ El-Khoury. 2020. "Femtosecond Photoemission Electron Microscopy of Surface Plasmon Polariton Beam Steering via Nanohole Arrays." The Journal of Chemical Physics 153, no. 8:081103. PNNL-SA-155077. doi:10.1063/5.0021032
  • Edgecomb JM, X Xie, Y Shao, PZ El-Khoury, GE Johnson, and V Prabhakaran. 2020. "Mapping localized peroxyl radical generation on a PEM fuel cell catalyst using integrated scanning electrochemical cell microspectroscopy." Frontiers in Chemistry 8. PNNL-SA-153799. doi:10.3389/fchem.2020.572563
  • El-Khoury PZ, and E Apra. 2020. "Spatially Resolved Mapping of Three-Dimensional Molecular Orientations with ~2 nm Spatial Resolution through Tip-Enhanced Raman Scattering." Journal of Physical Chemistry C 124, no. 31:17211-17217. PNNL-SA-153171. doi:10.1021/acs.jpcc.0c04263
  • El-Khoury PZ, and Z Schultz. 2020. "From SERS to TERS and beyond: molecules as probes of nanoscopic optical fields." Journal of Physical Chemistry C 124, no. 50:27267-27275. PNNL-SA-156138. doi:10.1021/acs.jpcc.0c08337
  • Krayev AV, S Krylyuk, R Ilic, A Hight Walker, A Bhattarai, AG Joly, and M Velicky, et al. 2020. "Comparable Enhancement of TERS Signals from WSe2 on Chromium and Gold." Journal of Physical Chemistry C 124, no. 16:8971-8977. PNNL-SA-140248. doi:10.1021/acs.jpcc.0c01298
  • O'Callahan BT, A Bhattarai, Z Schultz, and PZ El-Khoury. 2020. "Power-Dependent Dual Analyte Tip-Enhanced Raman Spectral Imaging." The Journal of Physical Chemistry C 124, no. 28:15454-15459. PNNL-SA-153512. doi:10.1021/acs.jpcc.0c05396
  • O'Callahan BT, K Park, IV Novikova, T Jian, C Chen, EA Muller, and PZ El-Khoury, et al. 2020. "In liquid infrared scattering scanning near-field optical microscopy for chemical and biological nanoimaging." Nano Letters 20, no. 6:4497-4504. PNNL-SA-152805. doi:10.1021/acs.nanolett.0c01291
  • Sloan-Dennison1 S, C Zoltowski, PZ El-Khoury, and Z Schultz. 2020. "Surface Enhanced Raman Scattering Selectivity in Proteins Arises from Electron Capture and Resonant Enhancement of Radical Species." Journal of Physical Chemistry C 124, no. 17:9548-9558. PNNL-SA-150358. doi:10.1021/acs.jpcc.0c01436
  • Wang C, Z Cheng, BT O'Callahan, KT Crampton, MR Jones, and PZ El-Khoury. 2020. "Tip-Enhanced Multipolar Raman Scattering." Journal of Physical Chemistry Letters 11, no. 7:2464-2469. PNNL-SA-151145. doi:10.1021/acs.jpclett.0c00559
  • Wang R, J Li, J Rigor, N Large, PZ El-Khoury, A Rogachev, and D Kurouski. 2020. "Direct Experimental Evidence of Hot-Carrier-Driven Chemical Processes in Tip-Enhanced Raman Spectroscopy (TERS)." Journal of Physical Chemistry C 124, no. 3:2238-2244. PNNL-SA-149743. doi:10.1021/acs.jpcc.9b12002
  • Wang Y, D Lu, ME Bowden, PZ El-Khoury, K Han, Z Deng, and J Xiao, et al. 2018. "Mechanism of Formation of Li7P3S11 Solid Electrolytes through Liquid Phase Synthesis." Chemistry of Materials 30, no. 3:990-997. PNNL-SA-130713. doi:10.1021/acs.chemmater.7b04842
  • Wang C, BT O'Callahan, D Kurouski, AV Krayev, and PZ El-Khoury. 2020. "The Prevalence of Anions at Plasmonic Nanojunctions: A Closer Look at P-Nitrothiophenol." Journal of Physical Chemistry Letters 11, no. 10:3809-3814. PNNL-SA-152463. doi:10.1021/acs.jpclett.0c01006
  • Wang C, BT O'Callahan, D Kurouski, AV Krayev, Z Schultz, and PZ El-Khoury. 2020. "Suppressing Molecular Charging, Nanochemistry, and Optical Rectification in the Tip-Enhanced Raman Geometry." Journal of Physical Chemistry Letters 11, no. 15:5890-5895. PNNL-SA-153064. doi:10.1021/acs.jpclett.0c01413

2019

  • Apra E, A Bhattarai, and PZ El-Khoury. 2019. "Gauging Molecular Orientation through Time Domain Simulations of Surface-Enhanced Raman Scattering." Journal of Physical Chemistry A 123, no. 32:7142-7147. PNNL-SA-145212. doi:10.1021/acs.jpca.9b06182
  • Bhattarai A, and PZ El-Khoury. 2019. "Nanoscale Chemical Reaction Imaging at the Solid-Liquid Interface via TERS." Journal of Physical Chemistry Letters 10, no. 11:2817-2822. PNNL-SA-141439. doi:10.1021/acs.jpclett.9b00935
  • Bhattarai A, AG Joly, AV Krayev, and PZ El-Khoury. 2019. "Taking the Plunge: Nanoscale Chemical Imaging of Functionalized Gold Triangles in H2O via TERS." Journal of Physical Chemistry C 123, no. 12:7376-7380. PNNL-SA-140448. doi:10.1021/acs.jpcc.9b00867
  • Bhattarai A, IV Novikova, and PZ El-Khoury. 2019. "Tip-Enhanced Raman Nanographs of Plasmonic Silver Nanoparticles." Journal of Physical Chemistry C 123, no. 45:27765-27769. PNNL-SA-146665. doi:10.1021/acs.jpcc.9b07811
  • Crampton KT, AG Joly, and PZ El-Khoury. 2019. "Direct Visualization of Counter-Propagating Surface Plasmons in Real Space-Time." Journal of Physical Chemistry Letters 10, no. 19:5694-5699. PNNL-SA-146664. doi:10.1021/acs.jpclett.9b02151
  • O'Callahan BT, M Hentschel, MB Raschke, PZ El-Khoury, and A Lea. 2019. "Ultrasensitive Tip- and Antenna-Enhanced Infrared Nanoscopy of Protein Complexes." Journal of Physical Chemistry C 123, no. 28:17505-17509. PNNL-SA-144661. doi:10.1021/acs.jpcc.9b05777
  • Wu H, Y Xu, X Ren, B Liu, M. Engelhard, MS Ding, and PZ El-Khoury, et al. 2019. "Polymer-in-"quasi-ionic liquid" electrolytes for high-voltage lithium metal batteries." Advanced Energy Materials 9, no. 41:1902108. PNNL-SA-144443. doi:10.1002/aenm.201902108

2018

  • Apra E, A Bhattarai, KT Crampton, EJ Bylaska, N Govind, WP Hess, and PZ El-Khoury. 2018. "Time Domain Simulations of Single Molecule Raman Scattering." Journal of Physical Chemistry A 122, no. 37:7437-7442. PNNL-SA-135554. doi:10.1021/acs.jpca.8b05912
  • Bhattarai A, KT Crampton, AG Joly, L Kovarik, WP Hess, and PZ El-Khoury. 2018. "Imaging the Optical Fields of Functionalized Silver Nanowires through Molecular TERS." The Journal of Physical Chemistry Letters 9, no. 24:7105-1709. PNNL-SA-139471. doi:10.1021/acs.jpclett.8b03324
  • Bhattarai A, AV Krayev, A Temiryazev, D Evplov, KT Crampton, WP Hess, and PZ El-Khoury. 2018. "Tip-Enhanced Raman Scattering from Nanopatterned Graphene and Graphene Oxide." Nano Letters 18, no. 6:4029-4033. PNNL-SA-134494. doi:10.1021/acs.nanolett.8b01690
  • Joly AG, PZ El-Khoury, and WP Hess. 2018. "Spatiotemporal Imaging of Surface Plasmons Using Two-Color Photoemission Electron Microscopy." Journal of Physical Chemistry C 122, no. 36:20981-20988. PNNL-SA-134196. doi:10.1021/acs.jpcc.8b05849
  • Joly AG, Y Gong, PZ El-Khoury, and WP Hess. 2018. "Surface Plasmon-Based Pulse Splitter and Polarization Multiplexer." Journal of Physical Chemistry Letters 9, no. 21:6164-6168. PNNL-SA-137832. doi:10.1021/acs.jpclett.8b02643
  • Mishra K, J Zheng, RL Patel, L Estevez, H Jia, L Luo, and PZ El-Khoury, et al. 2018. "High Performance Porous Si@C Anodes Synthesized by  Low Temperature Aluminothermic Reaction." Electrochimica Acta 269. PNNL-SA-130364. doi:10.1016/j.electacta.2018.02.166
  • O'Callahan BT, KT Crampton, IV Novikova, T Jian, C Chen, JE Evans, and MM Raschke, et al. 2018. "Imaging Nanoscale Heterogeneity in Ultrathin Biomimetic and Biological Crystals." Journal of Physical Chemistry C 122, no. 43:24891–24895. PNNL-SA-136203. doi:10.1021/acs.jpcc.8b06681
  • Yan F, L Liu, TR Walsh, Y Gong, PZ El-Khoury, Y Zhang, and Z Zhu, et al. 2018. "Controlled synthesis of highly-branched plasmonic gold nanoparticles through peptoid engineering." Nature Communications 9. PNNL-SA-118537. doi:10.1038/s41467-018-04789-2

2017

  • Bhattarai A, and PZ El-Khoury. 2017. "Imaging Localized Electric Fields with Nanometer Precision through Tip-Enhanced Raman Scattering." Chemical Communications 53, no. 53:7310-7313. PNNL-SA-125604. doi:10.1039/c7cc02593a
  • Bhattarai A, AG Joly, WP Hess, and PZ El-Khoury. 2017. "Visualizing Electric Fields at Au(111) Step Edges via Tip-Enhanced Raman Scattering." Nano Letters 17, no. 11:7131-7137. PNNL-SA-129323. doi:10.1021/acs.nanolett.7b04027
  • Fischer SA, E Apra, N Govind, WP Hess, and PZ El-Khoury. 2017. "Non-Equilibrium Chemical Effects in Single Molecule SERS Revealed by ab initio Molecular Dynamics Simulations." Journal of Physical Chemistry A 121, no. 6:1344-1350. PNNL-SA-122695. doi:10.1021/acs.jpca.6b12156
  • Gong Y, AG Joly, PZ El-Khoury, and WP Hess. 2017. "Polarization Directed Surface Plasmon Polariton Launching." Journal of Physical Chemistry Letters 8, no. 1:49-54. PNNL-SA-121461. doi:10.1021/acs.jpclett.6b02509
  • Gong Y, AG Joly, X Zhang, PZ El-Khoury, and WP Hess. 2017. "Surface Plasmon Coupling and Control using Spherical Cap Structures." Journal of Physical Chemistry Letters 8, no. 12:2695-2699. PNNL-SA-125352. doi:10.1021/acs.jpclett.7b00852
  • Novikova IV, CR Smallwood, Y Gong, D Hu, L Hendricks, JE Evans, and A Bhattarai, et al. 2017. "Multimodal Hyperspectral Optical Microscopy." Chemical Physics 498-499. PNNL-SA-120193. doi:10.1016/j.chemphys.2017.08.011

2016

  • Borin VA, SM Matveev, DS Budkina, PZ El-Khoury, and AN Tarnovsky. 2016. "Direct photoisomerization of CH2I2 vs CHBr3 in the gas phase: a joint 50 fs experimental and multireference resonance-theoretical study." Physical Chemistry Chemical Physics. PCCP 18, no. 41:28883-28892. PNNL-SA-119766. doi:10.1039/c6cp05129d
  • El-Khoury PZ, P Abellan, RL Chantry, Y Gong, AG Joly, IV Novikova, and JE Evans, et al. 2016. "The information content in single-molecule Raman nanoscopy." Advances in Physics: X 1, no. 1:35-54. PNNL-SA-114470. doi:10.1080/23746149.2016.1140010
  • El-Khoury PZ, P Abellan Baeza, Y Gong, FS Hage, J Cottom, AG Joly, and R Brydson, et al. 2016. "Visualizing Surface Plasmons with Photons, Photoelectrons, and Electrons." Analyst 141, no. 12:3562-3572. PNNL-SA-115897. doi:10.1039/c6an00308g
  • El-Khoury PZ, AG Joly, and WP Hess. 2016. "Hyperspectral Dark Field Optical Microscopy of Single Silver Nanospheres." Journal of Physical Chemistry C 120, no. 13:7295-7298. PNNL-SA-115933. doi:10.1021/acs.jpcc.6b02401
  • Fischer SA, TW Ueltschi, PZ El-Khoury, AL Mifflin, WP Hess, H Wang, and CJ Cramer, et al. 2016. "Infrared and Raman Spectroscopy from Ab Initio Molecular Dynamics and Static Normal Mode Analysis: The C-H Region of DMSO as a Case Study." Journal of Physical Chemistry B 120, no. 8:1429-1436. PNNL-SA-109387. doi:10.1021/acs.jpcb.5b03323
  • Gong Y, AG Joly, PZ El-Khoury, and WP Hess. 2016. "Enhanced Propagating Surface Plasmon Signal Detection." ACS Photonics 3, no. 12:2413-2419. PNNL-SA-121997. doi:10.1021/acsphotonics.6b00636
  • Ueltschi TW, SA Fischer, E Apra, AN Tarnovsky, N Govind, PZ El-Khoury, and WP Hess. 2016. "Time-Domain Simulations of Transient Species in Experimentally Relevant Environments." Journal of Physical Chemistry A 120, no. 4:556-561. PNNL-SA-114738. doi:10.1021/acs.jpca.5b11710

2015

  • El-Khoury PZ, GE Johnson, IV Novikova, Y Gong, AG Joly, JE Evans, and M Zamkov, et al. 2015. "Enhanced Raman Scattering from Aromatic Dithiols Electrosprayed into Plasmonic Nanojunctions." Faraday Discussions 184. PNNL-SA-109386. doi:10.1039/C5FD00036J
  • El-Khoury PZ, Y Gong, P Abellan, BW Arey, AG Joly, D Hu, and JE Evans, et al. 2015. "Tip-Enhanced Raman Nanographs: Mapping Topography and Local Electric Fields." Nano Letters 15, no. 4:2385-2390. PNNL-SA-106991. doi:10.1021/acs.nanolett.5b00609
  • Gong Y, AG Joly, PZ El-Khoury, and WP Hess. 2015. "Efficient Coupling and Transport of a Surface Plasmon at 780 nm in a Gold Nanostructure." In Plasmonics: Metallic Nanostructures and Their Optical Properties XIII, August 9, 2015, San Diego, California. Proceedings of the SPIE, edited by AD Boardman and DP Tsai, 9547, Paper No. 95470H. Bellingham, Washington:SPIE, the International Society for Optics and Photonics. PNNL-SA-111002.  doi:10.1117/12.2190449
  • Gong Y, AG Joly, D Hu, PZ El-Khoury, and WP Hess. 2015. "Ultrafast Imaging of Surface Plasmons Propagating on a Gold Surface." Nano Letters 15, no. 5:3472-3478. PNNL-SA-108438. doi:10.1021/acs.nanolett.5b00803

2014

  • Akula M, PZ El-Khoury, A Nag, and A Bhattacharya. 2014. "Selective Zn2+ sensing using a modified bipyridine complex." RSC Advances 4, no. 49:25605-25608. PNNL-SA-100766. doi:10.1039/C4RA00922C
  • El-Khoury PZ, and WP Hess. 2014. "Vibronic Raman Scattering at the Quantum Limit of Plasmons." Nano Letters 14, no. 7:4114-4118. PNNL-SA-102123. doi:10.1021/nl501690u
  • El-Khoury PZ, K Honkala, and WP Hess. 2014. "Electronic and Vibrational Properties of Meso-Tetraphenylporphyrin on Silver Substrates." Journal of Physical Chemistry A 118, no. 37:8115-8123. PNNL-SA-99895. doi:10.1021/jp412360b
  • El-Khoury PZ, E Khon, Y Gong, AG Joly, P Abellan, JE Evans, and ND Browning, et al. 2014. "Electric Field Enhancement in a Self-Assembled 2D Array of Silver Nanospheres." Journal of Chemical Physics 141, no. 21:Article No. 214308. PNNL-SA-105010. doi:10.1063/1.4902905
  • El-Khoury PZ, TW Ueltschi, AL Mifflin, D Hu, and WP Hess. 2014. "Frequency Resolved Nanoscale Chemical Imaging of 4,4'-Dimercaptostilbene on Silver." Journal of Physical Chemistry C 118, no. 47:27525-27530. PNNL-SA-100249. doi:10.1021/jp509082c
  • Gong Y, AG Joly, PZ El-Khoury, and WP Hess. 2014. "Interferometric Plasmonic Lensing with Nanohole Arrays." Journal of Physical Chemistry Letters 5, no. 24:4243-4248. PNNL-SA-106215. doi:10.1021/jz502296n
  • Gong Y, AG Joly, L Kong, PZ El-Khoury, and WP Hess. 2014. "High Brightness Plasmon-Enhanced Nanostructured Gold Photoemitters." Physical Review Applied 2, no. 6:Article No. 064012. PNNL-SA-100555. doi:10.1103/PhysRevApplied.2.064012
  • Gong Y, AG Joly, PZ El-Khoury, and WP Hess. 2014. "Nonlinear Photoemission Electron Micrographs of Plasmonic Nanoholes in Gold Thin Films." Journal of Physical Chemistry C 118, no. 44:25671-25676. PNNL-SA-105747. doi:10.1021/jp509900h

2013

  • El-Khoury PZ, EJ Bylaska, and WP Hess. 2013. "Time Domain Simulations of Chemical Bonding Effects in Surface-Enhanced Spectroscopy." Journal of Chemical Physics 139, no. 17:Article No. 174303. PNNL-SA-96865. doi:10.1063/1.4827455
  • El-Khoury PZ, D Hu, V Apkarian, and WP Hess. 2013. "Raman Scattering at Plasmonic Junctions Shorted by Conductive Molecular Bridges." Nano Letters 13, no. 4:1858-1861. PNNL-SA-93981. doi:10.1021/nl400733r
  • El-Khoury PZ, D Hu, and WP Hess. 2013. "Junction Plasmon-Induced Molecular Reorientation." Journal of Physical Chemistry Letters 4, no. 20:3435-3439. PNNL-SA-97929. doi:10.1021/jz401838b
  • El-Khoury PZ, and WP Hess. 2013. "Raman Scattering from 1,3-Propanedithiol at a Hot Spot: Theory Meets Experiment." Chemical Physics Letters 581. PNNL-SA-92753. doi:10.1016/j.cplett.2013.05.066
  • El-Khoury PZ, SJ Peppernick, D Hu, AG Joly, and WP Hess. 2013. "The Origin of Surface-Enhanced Raman Scattering of 4,4' -Biphenyldicarboxylate on Silver Substrates." Journal of Physical Chemistry C 117, no. 14:7260-7268. PNNL-SA-92092. doi:10.1021/jp401026x
  • Vilayur Ganapathy S, A Devaraj, RJ Colby, A Pandey, T Varga, V Shutthanandan, and S Manandhar, et al. 2013. "Subsurface Synthesis and Characterization of Ag Nanoparticles Embedded in MgO." Nanotechnology 24, no. 9:Article No. 095707. PNNL-SA-91351. doi:10.1088/0957-4484/24/9/095707
  • Vilayur Ganapathy S, MI Nandasiri, AG Joly, PZ El-Khoury, T Varga, GW Coffey, and B Schwenzer, et al. 2013. "Silver nanorod arrays for photocathode applications." Applied Physics Letters 103, no. 16:Article No. 161112. PNNL-SA-97756. doi:10.1063/1.4825262