Publications

74. H. Kang#, K. Park# and S. Ryu,* (#equal contribution) "Optical Imaging of Redox and Molecular Diffusion in 2D van der Waals Space", Acc. Chem. Res. 55, 44 (2022); [Link] [PDF]
73. K. Park and S. Ryu,* "Dual-Channel Charge Transfer Doping of Graphene by Sulfuric Acid", Bull. Korean Chem. Soc. in press (2022); [Link] [PDF]
72. S. W. Han, W. S. Yun, H. Kim, Y. Kim, D.-H. Kim, C. W. Ahn and S. Ryu "Hole Doping Effect of MoS2 via Electron Capture of He+ Ion Irradiation", Sci. Rep. 11, 23590 (2021); [Link] [PDF]
71. S. J. Yang, D. Kim, J. Choi, S. H. Kim, K. Park, S. Ryu and K. Cho, "Enhancing Thermoelectric Power Factor of 2D Organometal Halide Perovskites by Suppressing 2D/3D Phase Separation", Adv. Mater. 33, 2102797 (2021); [Link] [PDF]
70. S. Song, S. J. Yang, J. Choi, S. G. Han, K. Park, H. Lee, J. Min, S. Ryu and K. Cho, "Surface Stabilization of a Formamidinium Perovskite Solar Cell Using Quaternary Ammonium Salt", ACS Appl. Mater. & Interfaces 13, 37052 (2021); [Link] [PDF]
69. H. Kang and S. Ryu,* "Optical Imaging of Chemically and Geometrically Controlled Molecular Diffusion and Redox in 2D van der Waals Space", J. Phys. Chem. C 125, 16819 (2021); [Link] [PDF]
68. S. Koo, I. Park, K. Watanabe, T. Taniguchi, J. Shim and S. Ryu,* "Extraordinary Photostability and Davydov Splitting in BN-Sandwiched Single-Layer Tetracene Molecular Crystals", Nano Lett. 21, 6600 (2021); [Link] [PDF]
67. S. Lee, S. Kim, C. Park, W. Kim, S. Ryu and W. Choi, "Solar Denitrification Coupled with in situ Water Splitting", Energy Environ. Sci. 14, 4437 (2021); [Link] [PDF]
66. N. Kim, S. Choi, S.-J. Yang, J. Park, J.-H. Park, N. N. Nguyen, K. Park, S. Ryu, K. Cho and C.-J. Kim, "Graphene Nanoribbon Grids of Sub-10 nm Widths with High Electrical Connectivity", ACS Appl. Mater. & Interfaces 13, 28593 (2021); [Link] [PDF]
65. M. Song, H. Kang, D. Rhodes, B. Kim, J. Hone and S. Ryu,* "Optically Facet-Resolved Reaction Anisotropy in Two-Dimensional Transition Metal Dichalcogenides", 2D Materials 8, 035045 (2021); [Link] [PDF]
64. J.-I. Lee, S. Cho, T. T. Vu, S. Kim, S. Ryu, J. Moon and S. Park "Hybrid Polyion Complex Micelles Enabling High-Performance Lithium-Metal Batteries with Universal Carbonates", Energy Storage Mater. 38, 509 (2021); [Link] [PDF]
63. S. Kim, J. Lee, C. Lee and S. Ryu,* "Polarized Raman Spectra and Complex Raman Tensors of Antiferromagnetic Semiconductor CrPS4", J. Phys. Chem. C 125, 2691 (2021); [Link] [PDF]
62. W. Kim, J. Y. Ahn, J. Oh, J. H. Shim and S. Ryu,* "Second-Harmonic Young's Interference in Atom-Thin Heterocrystals", Nano Lett. 20, 8825 (2020); [Link] [PDF]
61. S. W. Jang, S. Dutta, A. Kumar, Y.-R. Hong, H. Kang, S. Lee, S. Ryu, W. Choi, and I. S. Lee, "Holey Pt Nanosheets on NiFe-Hydroxide Laminates: Synergistically Enhanced Electrocatalytic 2D Interface toward Hydrogen Evolution Reaction", ACS Nano 14, 10578 (2020); [Link] [PDF]
60. J. Choi, S. Koo, M. Song, D. Jung, S. Choi and S. Ryu,* "Varying Electronic Coupling at Graphene-Copper Interfaces Probed with Raman Spectroscopy", 2D Materials 7, 025006 (2020); [Link] [PDF]
59. K. Park#, H. Kang#, S. Koo, D. Lee and S. Ryu,* (#equal contribution) "Redox-Governed Charge Doping Dictated by Interfacial Diffusion in Two-Dimensional Materials", Nature Commun. 10, 4931 (2019); [Link] [PDF]
58. S. Kim, J. Lee, G. Jin, M.-H. Jo, C. Lee and S. Ryu,* "Crossover between Photochemical and Photothermal Oxidations of Atomically Thin Magnetic Semiconductor CrPS4", Nano Lett. 19, 4043 (2019); [Link] [PDF] 57. H. Jeon, T. Teraji, K. Watanabe, T. Taniguchi and S. Ryu,* "Lattice Vibrations of Single and Multi-Layer Isotopologic Graphene", Carbon 140, 449 (2018); [Link] [PDF]
56. Y. Kwon, K. Kim, W. Kim, S. Ryu and H. Cheong, "Variation of Photoluminescence Spectral Line Shape of Monolayer WS2", Curr. Appl. Phys. 18, 941 (2018); [Link] [PDF]
55. G. Ahn and S. Ryu,* "Reversible Sulfuric Acid Doping of Graphene Probed by in-situ Multi-Wavelength Raman Spectroscopy", Carbon 138, 257 (2018); [Link] [PDF] 54. S.-J. Kwon, T.-H. Han, T. Y. Ko, N. Li, S.-H. Bae, K. S. Kim, S. Ryu and T.-W. Lee, "Extremely Stable Graphene Electrodes Doped with Macromolecular Acid", Nature Commun. 9, 2037 (2018); [Link] [PDF]
53. Y. Jang, S.-J. Kwon, J. Shin, H. Jeong, W.-T. Hwang, J.-W. Kim, J. Koo, T. Y. Ko, S. Ryu, G. Wang, T.-W. Lee, and T. Lee, "Interface-Engineered Charge Transport Properties in Benzenedithol Molecular Electronic Junctions via Chemically p-doped Graphene Electrodes", ACS Appl. Mater. & Interfaces 9, 42043 (2017); [Link] [PDF]
52. Y. Ryu, W. Kim, S. Koo, H. Kang, K. Watanabe, T. Taniguchi, and S. Ryu,* "Interface-Confined Doubly Anisotropic Oxidation of Two-Dimensional MoS2", Nano Lett. 17, 7267 (2017); [Link] [PDF]
51. J. Lee, T. Y. Ko, J. H. Kim, H. Bark, B. Kang, S.-G. Jung, T. Park, Z. Lee, S. Ryu,* and C. Lee,* "Structural and Optical Properties of Single- and Few-Layer Magnetic Semiconductor CrPS4", ACS Nano 11, 10935 (2017); [Link] [PDF]
50. D.-G. Lee, H. Jeong, K.-W. Jeon, L. Zhang, K. Park, S. Ryu, J. Kim, and I. S. Lee, "Carbon thin-layer-coated manganese oxide nanocrystals as an effective support for high-performance Pt electrocatalysts stabilized at a metal–metal oxide–carbon triple junction", J. Mater. Chem. A 5, 22341 (2017); [Link] [PDF]
49. D. Luo, X. You, B.-W. Li, X. Chen, H. J. Park, M. Jang, T. Y. Ko, K. Wong, M. Yousaf, X. Chen, M. Huang, S. H. Lee, Z. Lee, H.-J. Shin, S. Ryu, S. K. Kwak, N. Park, R. R. Bacsa, W. Bacsa, R. S. Ruoff, "Role of Graphene in Water-Assisted Oxidation of Copper in Relation to Dry Transfer of Graphene", Chem. Mater. 29, 4546 (2017); [Link] [PDF]
48. P. K. Nayak, Y. Horbatenko, S. Ahn, G. Kim, J.-U. Lee, K. Y. Ma, A-R. Jang, H. Lim, D. Kim, S. Ryu, H. Cheong, N. Park, and H. S. Shin, "Probing Evolution of Twist-Angle-Dependent Interlayer Excitons in MoSe2/WSe2 van der Waals Heterostructures", ACS Nano 11, 4041 (2017); [Link] [PDF]
47. J. E. Lee, J. Jung, T. Y. Ko, S. Kim, S.-I. Kim, J. Nah, S. Ryu, K. T. Nam and M. H. Lee, "Catalytic synergy effect of MoS2/reduced graphene oxide hybrids for a highly efficient hydrogen evolution reaction", RSC Adv. 7, 5480 (2017); [Link] [PDF]
46. T. Y. Ko, A. Jeong, W. Kim, J. Lee, Y. Kim, J. E. Lee, G. H. Ryu, K. Park, D. Kim, Z. Lee, M. H. Lee, C. Lee and S. Ryu,* "On-Stack Two-Dimensional Conversion of MoS2 into MoO3", 2D Materials 4, 014003 (2017); [Link] [PDF]
45. X. Zhang, Y. Huang, S. Chen, N. Y. Kim, W. Kim, D. Schilter, M. Biswal, B. Li, Z. Lee, S. Ryu, C. W. Bielawski, W. S. Bacsa, and R. S. Ruoff, "Birch-Type Hydrogenation of Few-Layer Graphenes: Products and Mechanistic Implications", J. Am. Chem. Soc. 138, 14980 (2016); [Link] [PDF]
44. H. Kwon, S. W. Seo, T. G. Kim, E. S. Lee, P. T. Lanh, S. Yang, S. Ryu,* J. W. Kim,* "Ultrathin and Flat Layer Black Phosphorus Fabricated by Reactive Oxygen and Water Rinse", ACS Nano 10, 8723 (2016); [Link] [PDF]
43. S. Kim and S. Ryu,* "Thickness-Dependent Native Strain in Graphene Membranes Visualized by Raman Spectroscopy ", Carbon 100, 283 (2016); [Link] [PDF]
42. S.-S. Kim, M. J. Park, J.-H. Kim, G. Ahn, S. Ryu, B. H. Hong, and B.-H. Sohn, "Strain-Assisted Wafer-Scale Nanoperforation of Single-Layer Graphene by Arrayed Pt Nanoparticles", Chem. Mater. 27, 7003 (2015); [Link] [PDF]
41. D.-S. Kim, H. Kwon, A. Y. Nikitin, S. Ahn, L. Martín-Moreno, F. J. García-Vidal, S. Ryu, H. Min, and Z. H. Kim, "Stacking Structures of Few-Layer Graphene Revealed by Phase-Sensitive Infrared Nanoscopy", ACS Nano 9, 6765 (2015); [Link] [PDF]
40. K. Park and S. Ryu,* "Direction-Controlled Chemical Doping for Reversible G-Phonon Mixing in ABC Trilayer", Sci. Rep. 5, 8707 (2015); [Link] [PDF]
39. Y.-J. Yu, K. S. Kim, J. Nam, S. R. Kwon, H. Byun, K. Lee, J.-H. Ryou, R. D. Dupuis, J. Kim, G. Ahn, S. Ryu, M.-Y. Ryu and J. S. Kim, "Temperature-Dependent Resonance Energy Transfer from Semiconductor Quantum Wells to Graphene", Nano Lett. 15, 896 (2015); [Link] [PDF]
38. P. Joo, K. Jo, G. Ahn, D. Voiry, H. Y. Jeong, S. Ryu, M. Chhowalla, and B.-S. Kim,* "Functional Polyelectrolyte Nanospaced MoS2 Multilayers for Enhanced Photoluminescence", Nano Lett. 14, 6456 (2014); [Link] [PDF]
37. Y. Ryu, M. K. Park, and S. Ryu,* "Thermal Modulation of Photoluminescence from Single-Layer MoS2", Bull. Korean Chem. Soc. 35, 3077 (2014); [Link] [PDF]
36. G. Park, S. K. Park, J. Han, T. Y. Ko, S. Lee, J. Oh, S. Ryu, H. S. Park and S. Park, "Finely Tuning Oxygen Functional Groups of Graphene Materials and Optimizing Oxygen Levels for Capacitors ", RSC Adv. 4, 36377 (2014); [Link] [PDF]
35. D. Lee, G. Ahn and S. Ryu,* "Two-Dimensional Water Diffusion at a Graphene-Silica Interface", J. Am. Chem. Soc. 136, 6634 (2014); [Link] [PDF]
34. Y. Kim, D. Cho, S. Ryu and C. Lee, "Tuning Doping and Strain in Graphene by Microwave-Induced Annealing", Carbon 67, 673 (2014); [Link] [PDF]
33. J. Hong, M. K. Park, E. J. Lee, D. Lee, D. S. Hwang and S. Ryu,* "Origin of New Broad Raman D and G Peaks in Annealed Graphene", Sci. Rep. 3, 2700 (2013); [Link] [PDF]
32. S. W. Han, Y. H. Hwang, S.-H. Kim, W. S. Yun, J. D. Lee, M. G. Park, S. Ryu, J. S. Park, D.-H. Yoo, S.-P. Yoon, S. C. Hong, K. S. Kim, and Y. S. Park, "Controlling Ferromagnetic Easy Axis in a Layered MoS2 Single Crystal", Phys. Rev. Lett. 110, 247201 (2013); [Link] [PDF]
31. G. Ahn , H. R. Kim , T. Y. Ko , K. Choi , K. Watanabe , T. Taniguchi , B. H. Hong , and S. Ryu,* "Optical Probing of the Electronic Interaction between Graphene and Hexagonal Boron Nitride", ACS Nano 7, 1533 (2013); [Link] [PDF]
30. S.-W. Min, H. S. Lee, H. J. Choi, M. K. Park, T. Nam, H. Kim, S. Ryu and S. Im, "Nanosheet Thickness-Modulated MoS2 Dielectric Property Evidenced by Field-Effect Transistor Performance", Nanoscale 5, 548 (2013); [Link] [PDF]
29. M. J. Lee, J. S. Choi, J.-S. Kim, I.-S. Byun, D. H. Lee, S. Ryu, C. Lee, and B. H. Park, "Characteristics and Effects of Diffused Water Between Graphene and a SiO2 Substrate", Nano Res. 5, 710 (2012); [Link] [PDF]
28. H. S. Lee, S.-W. Min, M. K. Park, Y. T. Lee, P. J. Jeon, J. H. Kim, S. Ryu and S. Im, " MoS2 Nanosheets for Top-Gate Nonvolatile Memory Transistor Channel", Small 8, 3111 (2012); [Link] [PDF]
27. S. W. Han, G.-B. Cha, E. Frantzeskakis, I. Razado-Colambo, J. Avila, Y. S. Park, D. Kim, J. Hwang, J. S. Kang, S. Ryu, W. S. Yun, S. C. Hong, and M. C. Asensio, "Band-Gap Expansion in the Surface-Localized Electronic Structure of MoS2(0002)", Phys. Rev. B 86, 115105 (2012); [Link] [PDF]
26. J. E. Lee, G. Ahn, J. Shim, Y. S. Lee, and S. Ryu,* "Optical Separation of Mechanical Strain from Charge Doping in Graphene", Nature Commun. 3, 1024 (2012); [Link] [PDF]
25. H. S. Lee, S. Min, Y. Chang, M. K. Park, T. Nam, H. Kim, J. H. Kim, S. Ryu, and S. Im, “MoS2 Nanosheet Phototransistors with Thickness-Modulated Optical Energy Gap”, Nano Lett. 12, 3695 (2012); [Link] [PDF]
24. G. Ahn, H. R. Kim, B. H. Hong, and S. Ryu,* “Raman Spectroscopy Study on the Reactions of UV-Generated Oxygen Atoms with Single-Layer Graphene on SiO­2/Si Substrates”, Carbon Lett. 13, 34 (2012); [Link] [PDF]
23. J. Shim, C. H. Lui, T. Y. Ko, Y.-J. Yu, P. Kim, T. F. Heinz, and S. Ryu,* “Water-Gated Charge Doping of Graphene Induced by Mica Substrates”, Nano Lett. 12, 648 (2012); [Link] [PDF]
22. H. Kwon, K. Hwang, J. Park, S. Ryu, and S. K. Kim, “Electron Solvation and Solvation-Induced Crystallization of an Ammonia Film on Ag(111) Studied by 2-Photon Photoemission”, Phys. Chem. Chem. Phys. 13, 17785 (2011); [Link] [PDF]
21. S. W. Han, H. Kwon, S. K. Kim, S. Ryu, W. S. Yun, D. H. Kim, J. H. Hwang, J.-S. Kang, J. Baik, H. J. Shin, and S. C. Hong, “Band-Gap Transition Induced by Interlayer van der Waals Interaction in MoS2”, Phys. Rev. B 84, 045409 (2011); [Link] [PDF]
20. S. Ryu,* J. Maultzsch, M. Y. Han, P. Kim, and L. E. Brus, “Raman Spectroscopy of Lithographically Patterned Graphene Nanoribbons”, ACS Nano 5, 4123 (2011); [Link] [PDF]
19. S. Ryu, Li Liu, S. Berciaud, Y.-J. Yu, H. Liu, P. Kim, G. W. Flynn, and L. E. Brus, “Atmospheric Oxygen Binding and Hole Doping in Deformed Graphene on a SiO2 Substrate”, Nano Lett. 10, 4944 (2010); [Link] [PDF]
18. J. Song, T. Y. Ko, and S. Ryu,* “Raman Spectroscopy Study of Annealing-Induced Effects on Graphene Prepared by Micromechanical Exfoliation”, Bull. Korean Chem. Soc. 31, 2679 (2010); [Link] [PDF]
17. C. Lee, H. Yan, L. E. Brus, T. F. Heinz, J. Hone, and S. Ryu,* “Anomalous Lattice Vibrations of Single- and Few-Layer MoS2”, ACS Nano 4, 2695 (2010); [Link] [PDF]
16. S. Vukelic, P. Kongsuwan, S. Ryu and Y. L. Yao, "Ultrafast Laser Induced Structural Modification of Fused Silica—Part II: Spatially Resolved and Decomposed Raman Spectral Analysis", J. Manuf. Sci. E. 132, 061013 (2010); [Link] [PDF]
15. H. Liu, S. Ryu, Z. Chen, M. L. Steigerwald, C. Nuckolls, and L. E. Brus, “Photochemical Reactivity of Graphene”, J. Am. Chem. Soc. 131, 17099 (2009); [Link] [PDF]
14. Y.-J. Yu, Y. Zhao, S. Ryu, L. E. Brus, K. S. Kim, and P. Kim, “Tuning the Graphene Work Function by Electric Field Effect”, Nano Lett. 9, 3430 (2009); [Link] [PDF]
13. E. Stolyarova, D. Stolyarov, K. Bolotin, S. Ryu, L. Liu, K. T. Rim, M. Klima, M.Hybertsen, I. Pogorelsky, I. Pavlishin, K. Kusche, J. Hone, P. Kim, H. L. Stormer, V. Yakimenko, and G. Flynn, “Observation of Graphene Bubbles and Effective Mass Transport under Graphene Films”, Nano Lett. 9, 332 (2009); [Link] [PDF]
12. S. Berciaud, S. Ryu, L. E. Brus, and T. F. Heinz, “Probing the Intrinsic Properties of Exfoliated Graphene: Raman Spectroscopy of Free-Standing Monolayers”, Nano Lett. 9, 346 (2009); [Link] [PDF]
11. S. Ryu, M. Y. Han, J. Maultzsch, M. L. Steigerwald, T. F. Heinz, P. Kim, and L. E. Brus, “Reversible Basal Plane Hydrogenation of Graphene”, Nano Lett. 8, 4597 (2008); [Link] [PDF]
10. L. Liu,+ S. Ryu,+ M. R. Tomasik, E. Stolyarova, N. J. Jung, M. S. Hybertsen, M. L. Steigerwald, L. E. Brus, and G. W. Flynn, “Graphene Oxidation: Thickness Dependent Etching and Strong Chemical Doping”, Nano Lett. 8, 1965 (2008) (+equal authorship); [Link] [PDF]
9. J. S. Lee, S. Ryu, K. Yoo, J. Kim , I. S. Choi, and W. S. Yun, “Local Inhomogeneity in Gate Hysteresis of Carbon Nanotube Field-effect Transistors Investigated by Scanning Gate Microscopy”, Ultramicroscopy 108, 1045 (2008); [Link] [PDF]
8. J. S. Lee, S. Ryu, K. Yoo, I. S. Choi, W. S. Yun, and J. Kim, “Origin of Gate Hysteresis in Carbon Nanotube Field-Effect Transistors”, J. Phys. Chem. C 111, 12504 (2007); [Link] [PDF]
7. E. Stolyarova, K. T. Rim, S. Ryu, J. Maultzsch, P. Kim, L. E. Brus, T. F. Heinz, M. S. Hybertsen, and G. W. Flynn, “High-resolution Scanning Tunneling Microscopy Imaging of Mesoscopic Graphene Sheets on an Insulating Surface”, Proc. Natl. Acad. Sci. USA 104, 9209 (2007); [Link] [PDF]
6. S. Ryu, J. Chang, and S. K. Kim, “Hot Electrons at Metal-organic interface: Time-resolved Two Photon Photoemission Study of Phenol on Ag(111)”, J. Vac. Sci. Technol. A 24, 1454 (2006); [Link] [PDF]
5. S. Ryu, J. Chang, H. Kwon, and S. K. Kim, “Dynamics of Solvated Electron Transfer in Thin Ice Film Leading to a Large Enhancement in Photodissociation of CFCl3”, J. Am. Chem. Soc. 128, 3500 (2006); [Link] [PDF]
4. S. Ryu, J. Chang, and S. K. Kim, “Interfacial Electron Dynamics and Hot-electron-driven Surface Photochemistry of Carbon Tetrachloride on Ag(111)”, J. Chem. Phys. 123, 114710 (2005); [Link] [PDF]
3. J. Lee,+ S. Ryu,+ J. Chang, S. Kim, and S. K. Kim, “Direct Observation of an Intermediate State for a Surface Photochemical Reaction Initiated by Hot Electron Transfer”, J. Phys. Chem. B 109, 14481 (2005) (+equal authorship); [Link] [PDF]
2. J. Lee, S. Ryu, J. S. Ku, and S. K. Kim, “Charge Transfer Photodissociation of Phenol on Ag(111)”, J. Chem. Phys. 115, 10518 (2001); [Link] [PDF]
1. J. Lee, S. Ryu, and S. K. Kim, “The Adsorption and Photochemistry of Phenol on Ag(111)”, Surf. Sci. 481, 163 (2001); [Link] [PDF]