Experimental Determination of the Ionization Energies of MoSe2, WS2, and MoS2 on SiO2 Using Photoemission Electron Microscopy

Keyshar, Kunttal; Berg, Morgann; Zhang, Xiang; Vajtai, Robert; Gupta, Gautam; Chan, Calvin K.; Beechem, Thomas E.; Ajayan, Pulickel M.; Mohite, Aditya D.; Ohta, Taisuke

doi:10.1021/acsnano.7b03242

Experimental Determination of the Ionization Energies of MoSe₂, WS₂, and MoS₂ on SiO₂ Using Photoemission Electron Microscopy

Journal Article · Wed Jul 19 00:00:00 EDT 2017 · ACS Nano

DOI:https://doi.org/10.1021/acsnano.7b03242· OSTI ID:1399563

Keyshar, Kunttal ^[1]; Berg, Morgann ^[2]; Zhang, Xiang ^[1]; Vajtai, Robert ^[1]; Gupta, Gautam ^[3]; Chan, Calvin K. ^[2]; Beechem, Thomas E. ^[2]; Ajayan, Pulickel M. ^[1]; ^[3]; ^[2]

Rice Univ., Houston, TX (United States)
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Here, the values of the ionization energies of transition metal dichalcogenides (TMDs) are needed to assess their potential usefulness in semiconductor heterojunctions for high-performance optoelectronics. Here, we report on the systematic determination of ionization energies for three prototypical TMD monolayers (MoSe₂, WS₂, and MoS₂) on SiO₂ using photoemission electron microscopy with deep ultraviolet illumination. The ionization energy displays a progressive decrease from MoS₂, to WS₂, to MoSe₂, in agreement with predictions of density functional theory calculations. Combined with the measured energy positions of the valence band edge at the Brillouin zone center, we deduce that, in the absence of interlayer coupling, a vertical heterojunction comprising any of the three TMD monolayers would form a staggered (type-II) band alignment. This band alignment could give rise to long-lived interlayer excitons that are potentially useful for valleytronics or efficient electron–hole separation in photovoltaics.

View Accepted Manuscript (DOE)

Research Organization:: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

Sponsoring Organization:: USDOE Office of Energy Efficiency and Renewable Energy (EERE)

Grant/Contract Number:: AC04-94AL85000

OSTI ID:: 1399563

Report Number(s):: SAND--2017-8462J; 656074

Journal Information:: ACS Nano, Journal Name: ACS Nano Journal Issue: 8 Vol. 11; ISSN 1936-0851

Publisher:: American Chemical Society (ACS)Copyright Statement

Country of Publication:: United States

Language:: English

References (60)

Electric-Field Screening in Atomically Thin Layers of MoS ₂ : the Role of Interlayer Coupling Castellanos-Gomez, Andres; Cappelluti, Emmanuele; Roldán, Rafael Advanced Materials, Vol. 25, Issue 6 https://doi.org/10.1002/adma.201203731	journal	November 2012
Method for the analysis of nonselective spectra of optically stimulated electron emission from irradiated dielectrics Zatsepin, A. F.; Biryukov, D. Yu.; Kortov, V. S. physica status solidi (a), Vol. 202, Issue 10 https://doi.org/10.1002/pssa.200420054	journal	August 2005
Computational 2D Materials Database: Electronic Structure of Transition-Metal Dichalcogenides and Oxides Rasmussen, Filip A.; Thygesen, Kristian S. The Journal of Physical Chemistry C, Vol. 119, Issue 23 https://doi.org/10.1021/acs.jpcc.5b02950	journal	June 2015
Stacking-Dependent Interlayer Coupling in Trilayer MoS ₂ with Broken Inversion Symmetry Yan, Jiaxu; Xia, Juan; Wang, Xingli Nano Letters, Vol. 15, Issue 12 https://doi.org/10.1021/acs.nanolett.5b03597	journal	November 2015
Fluorescence Concentric Triangles: A Case of Chemical Heterogeneity in WS ₂ Atomic Monolayer Liu, Hongwei; Lu, Junpeng; Ho, Kenneth Nano Letters, Vol. 16, Issue 9 https://doi.org/10.1021/acs.nanolett.6b02111	journal	August 2016
Chemical Vapor Deposition Synthesized Atomically Thin Molybdenum Disulfide with Optoelectronic-Grade Crystalline Quality Bilgin, Ismail; Liu, Fangze; Vargas, Anthony ACS Nano, Vol. 9, Issue 9 https://doi.org/10.1021/acsnano.5b02019	journal	August 2015
Van der Waals Epitaxy of Two-Dimensional MoS ₂ –Graphene Heterostructures in Ultrahigh Vacuum Miwa, Jill A.; Dendzik, Maciej; Grønborg, Signe S. ACS Nano, Vol. 9, Issue 6 https://doi.org/10.1021/acsnano.5b02345	journal	May 2015
Scanning Tunneling Microscopy and Spectroscopy of Air Exposure Effects on Molecular Beam Epitaxy Grown WSe ₂ Monolayers and Bilayers Park, Jun Hong; Vishwanath, Suresh; Liu, Xinyu ACS Nano, Vol. 10, Issue 4 https://doi.org/10.1021/acsnano.5b07698	journal	March 2016
Revealing Defect-State Photoluminescence in Monolayer WS ₂ by Cryogenic Laser Processing He, Zhengyu; Wang, Xiaochen; Xu, Wenshuo ACS Nano, Vol. 10, Issue 6 https://doi.org/10.1021/acsnano.6b00714	journal	May 2016
Microsteganography on WS ₂ Monolayers Tailored by Direct Laser Painting Venkatakrishnan, Ashwin; Chua, Hou; Tan, Pinxi ACS Nano, Vol. 11, Issue 1 https://doi.org/10.1021/acsnano.6b07118	journal	January 2017
Detailed photocurrent spectroscopy of the semiconducting group VIB transition metal dichalcogenides Kam, K. K.; Parkinson, B. A. The Journal of Physical Chemistry, Vol. 86, Issue 4 https://doi.org/10.1021/j100393a010	journal	February 1982
Stable, Single-Layer MX ₂ Transition-Metal Oxides and Dichalcogenides in a Honeycomb-Like Structure Ataca, C.; Şahin, H.; Ciraci, S. The Journal of Physical Chemistry C, Vol. 116, Issue 16 https://doi.org/10.1021/jp212558p	journal	April 2012
Electronic Band Structures of Molybdenum and Tungsten Dichalcogenides by the GW Approach Jiang, Hong The Journal of Physical Chemistry C, Vol. 116, Issue 14 https://doi.org/10.1021/jp300079d	journal	March 2012
Integrated Circuits Based on Bilayer MoS₂ Transistors Wang, Han; Yu, Lili; Lee, Yi-Hsien Nano Letters, Vol. 12, Issue 9, p. 4674-4680 https://doi.org/10.1021/nl302015v	journal	January 2012
Direct Imaging of Band Profile in Single Layer MoS ₂ on Graphite: Quasiparticle Energy Gap, Metallic Edge States, and Edge Band Bending Zhang, Chendong; Johnson, Amber; Hsu, Chang-Lung Nano Letters, Vol. 14, Issue 5 https://doi.org/10.1021/nl501133c	journal	April 2014
Bandgap, Mid-Gap States, and Gating Effects in MoS ₂ Lu, Chih-Pin; Li, Guohong; Mao, Jinhai Nano Letters, Vol. 14, Issue 8 https://doi.org/10.1021/nl501659n	journal	July 2014
Size-Dependent Valence and Conduction Band-Edge Energies of Semiconductor Nanocrystals Jasieniak, Jacek; Califano, Marco; Watkins, Scott E. ACS Nano, Vol. 5, Issue 7 https://doi.org/10.1021/nn201681s	journal	June 2011
Single-Layer MoS₂ Phototransistors Yin, Zongyou; Li, Hai; Li, Hong ACS Nano, Vol. 6, Issue 1, p. 74-80 https://doi.org/10.1021/nn2024557	journal	December 2011
Integrated Circuits and Logic Operations Based on Single-Layer MoS ₂ Radisavljevic, Branimir; Whitwick, Michael Brian; Kis, Andras ACS Nano, Vol. 5, Issue 12 https://doi.org/10.1021/nn203715c	journal	November 2011
Controlled Growth of High-Quality Monolayer WS ₂ Layers on Sapphire and Imaging Its Grain Boundary Zhang, Yu; Zhang, Yanfeng; Ji, Qingqing ACS Nano, Vol. 7, Issue 10 https://doi.org/10.1021/nn403454e	journal	September 2013
Nonblinking, Intense Two-Dimensional Light Emitter: Monolayer WS ₂ Triangles Peimyoo, Namphung; Shang, Jingzhi; Cong, Chunxiao ACS Nano, Vol. 7, Issue 12 https://doi.org/10.1021/nn4046002	journal	November 2013
Defect-Dominated Doping and Contact Resistance in MoS ₂ McDonnell, Stephen; Addou, Rafik; Buie, Creighton ACS Nano, Vol. 8, Issue 3 https://doi.org/10.1021/nn500044q	journal	February 2014
Chemical Vapor Deposition Growth of Crystalline Monolayer MoSe₂ Wang, Xingli; Gong, Yongji; Shi, Gang ACS Nano, Vol. 8, Issue 5, p. 5125-5131 https://doi.org/10.1021/nn501175k	journal	April 2014
Van der Waals heterostructures Geim, A. K.; Grigorieva, I. V. Nature, Vol. 499, Issue 7459, p. 419-425 https://doi.org/10.1038/nature12385	journal	July 2013
Efficient hydrogen evolution in transition metal dichalcogenides via a simple one-step hydrazine reaction Cummins, Dustin R.; Martinez, Ulises; Sherehiy, Andriy Nature Communications, Vol. 7, Issue 1 https://doi.org/10.1038/ncomms11857	journal	June 2016
Determination of band alignment in the single-layer MoS2/WSe2 heterojunction Chiu, Ming-Hui; Zhang, Chendong; Shiu, Hung-Wei Nature Communications, Vol. 6, Issue 1 https://doi.org/10.1038/ncomms8666	journal	July 2015
Universal energy-level alignment of molecules on metal oxides Greiner, Mark T.; Helander, Michael G.; Tang, Wing-Man Nature Materials, Vol. 11, Issue 1 https://doi.org/10.1038/nmat3159	journal	November 2011
Lateral heterojunctions within monolayer MoSe₂–WSe₂ semiconductors Huang, Chunming; Wu, Sanfeng; Sanchez, Ana M. Nature Materials, Vol. 13, Issue 12, p. 1096-1101 https://doi.org/10.1038/nmat4064	journal	August 2014
Vertical and in-plane heterostructures from WS₂/MoS₂ monolayers Gong, Yongji; Lin, Junhao; Wang, Xingli Nature Materials, Vol. 13, Issue 12, p. 1135-1142 https://doi.org/10.1038/nmat4091	journal	September 2014
The role of electronic coupling between substrate and 2D MoS2 nanosheets in electrocatalytic production of hydrogen Voiry, Damien; Fullon, Raymond; Yang, Jieun Nature Materials, Vol. 15, Issue 9 https://doi.org/10.1038/nmat4660	journal	June 2016
Controllable Growth of Large–Size Crystalline MoS2 and Resist-Free Transfer Assisted with a Cu Thin Film Lin, Ziyuan; Zhao, Yuda; Zhou, Changjian Scientific Reports, Vol. 5, Issue 1 https://doi.org/10.1038/srep18596	journal	December 2015
The Effect of Preparation Conditions on Raman and Photoluminescence of Monolayer WS2 McCreary, Kathleen M.; Hanbicki, Aubrey T.; Singh, Simranjeet Scientific Reports, Vol. 6, Issue 1 https://doi.org/10.1038/srep35154	journal	October 2016
Fermi level, work function and vacuum level Kahn, Antoine Materials Horizons, Vol. 3, Issue 1 https://doi.org/10.1039/C5MH00160A	journal	January 2016
Repairing sulfur vacancies in the MoS ₂ monolayer by using CO, NO and NO ₂ molecules Ma, Dongwei; Wang, Qinggao; Li, Tingxian Journal of Materials Chemistry C, Vol. 4, Issue 29 https://doi.org/10.1039/C6TC01746K	journal	January 2016
Efficient work-function engineering of solution-processed MoS2 thin-films for novel hole and electron transport layers leading to high-performance polymer solar cells Yun, Jin-Mun; Noh, Yong-Jin; Yeo, Jun-Seok Journal of Materials Chemistry C, Vol. 1, Issue 24 https://doi.org/10.1039/c3tc30504j	journal	January 2013
The origin of contrast in the imaging of doped areas in silicon by slow electrons Frank, Luděk; Müllerová, Ilona; Valdaitsev, Dimitrii A. Journal of Applied Physics, Vol. 100, Issue 9 https://doi.org/10.1063/1.2364044	journal	November 2006
Band offsets and heterostructures of two-dimensional semiconductors Kang, Jun; Tongay, Sefaattin; Zhou, Jian Applied Physics Letters, Vol. 102, Issue 1 https://doi.org/10.1063/1.4774090	journal	January 2013
Surface potential and interlayer screening effects of few-layer MoS ₂ nanoflakes Li, Yang; Xu, Cheng-Yan; Zhen, Liang Applied Physics Letters, Vol. 102, Issue 14 https://doi.org/10.1063/1.4801844	journal	April 2013
Band alignment of two-dimensional transition metal dichalcogenides: Application in tunnel field effect transistors Gong, Cheng; Zhang, Hengji; Wang, Weihua Applied Physics Letters, Vol. 103, Issue 5 https://doi.org/10.1063/1.4817409	journal	July 2013
Operando x-ray photoelectron emission microscopy for studying forward and reverse biased silicon p-n junctions Barrett, N.; Gottlob, D. M.; Mathieu, C. Review of Scientific Instruments, Vol. 87, Issue 5 https://doi.org/10.1063/1.4948597	journal	May 2016
Strong interlayer coupling in van der Waals heterostructures built from single-layer chalcogenides Fang, H.; Battaglia, C.; Carraro, C. Proceedings of the National Academy of Sciences, Vol. 111, Issue 17 https://doi.org/10.1073/pnas.1405435111	journal	April 2014
Spatially resolved, energy-filtered imaging of core level and valence band photoemission of highly p and n doped silicon patterns Barrett, N.; Zagonel, L. F.; Renault, O. Journal of Physics: Condensed Matter, Vol. 21, Issue 31 https://doi.org/10.1088/0953-8984/21/31/314015	journal	July 2009
Direct and Indirect Excitation Processes in Photoelectric Emission from Silicon Gobeli, G. W.; Allen, F. G. Physical Review, Vol. 127, Issue 1 https://doi.org/10.1103/PhysRev.127.141	journal	July 1962
Photoemission studies of layered transition-metal dichalcogenides: Mo S 2 McMenamin, J. C.; Spicer, W. E. Physical Review B, Vol. 16, Issue 12 https://doi.org/10.1103/PhysRevB.16.5474	journal	December 1977
Giant spin-orbit-induced spin splitting in two-dimensional transition-metal dichalcogenide semiconductors Zhu, Z. Y.; Cheng, Y. C.; Schwingenschlögl, U. Physical Review B, Vol. 84, Issue 15 https://doi.org/10.1103/PhysRevB.84.153402	journal	October 2011
Tunable band gaps in bilayer transition-metal dichalcogenides Ramasubramaniam, Ashwin; Naveh, Doron; Towe, Elias Physical Review B, Vol. 84, Issue 20 https://doi.org/10.1103/PhysRevB.84.205325	journal	November 2011
Nature and evolution of the band-edge states in MoS 2 : From monolayer to bulk Padilha, J. E.; Peelaers, H.; Janotti, A. Physical Review B, Vol. 90, Issue 20 https://doi.org/10.1103/PhysRevB.90.205420	journal	November 2014
Band alignment of two-dimensional semiconductors for designing heterostructures with momentum space matching Özçelik, V. Ongun; Azadani, Javad G.; Yang, Ce Physical Review B, Vol. 94, Issue 3 https://doi.org/10.1103/PhysRevB.94.035125	journal	July 2016
Layer dependence of the electronic band alignment of few-layer Mo S 2 on Si O 2 measured using photoemission electron microscopy Berg, Morgann; Keyshar, Kunttal; Bilgin, Ismail Physical Review B, Vol. 95, Issue 23 https://doi.org/10.1103/PhysRevB.95.235406	journal	June 2017
Atomically Thin MoS2 A New Direct-Gap Semiconductor Mak, Kin Fai; Lee, Changgu; Hone, James Physical Review Letters, Vol. 105, Issue 13, Article No.136805 https://doi.org/10.1103/PhysRevLett.105.136805	journal	September 2010
Coupled Spin and Valley Physics in Monolayers of MoS 2 and Other Group-VI Dichalcogenides Xiao, Di; Liu, Gui-Bin; Feng, Wanxiang Physical Review Letters, Vol. 108, Issue 19 https://doi.org/10.1103/PhysRevLett.108.196802	journal	May 2012
One-Dimensional Metallic Edge States in MoS 2 Bollinger, M. V.; Lauritsen, J. V.; Jacobsen, K. W. Physical Review Letters, Vol. 87, Issue 19 https://doi.org/10.1103/PhysRevLett.87.196803	journal	October 2001
Determination of band offsets, hybridization, and exciton binding in 2D semiconductor heterostructures Wilson, Neil R.; Nguyen, Paul V.; Seyler, Kyle Science Advances, Vol. 3, Issue 2 https://doi.org/10.1126/sciadv.1601832	journal	February 2017
Identification of Active Edge Sites for Electrochemical H₂ Evolution from MoS₂ Nanocatalysts Jaramillo, T. F.; Jorgensen, K. P.; Bonde, J. Science, Vol. 317, Issue 5834, p. 100-102 https://doi.org/10.1126/science.1141483	journal	July 2007
The valley Hall effect in MoS2 transistors Mak, K. F.; McGill, K. L.; Park, J. Science, Vol. 344, Issue 6191 https://doi.org/10.1126/science.1250140	journal	June 2014
Near-unity photoluminescence quantum yield in MoS2 Amani, M.; Lien, D. -H.; Kiriya, D. Science, Vol. 350, Issue 6264 https://doi.org/10.1126/science.aad2114	journal	November 2015
Photoemission and luminescence properties of quartz glass implanted with Cu+ ions Zatsepin, A. F.; Kortov, V. S.; Gavrilov, N. V. Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques, Vol. 2, Issue 3 https://doi.org/10.1134/S1027451008030233	journal	June 2008
Distinct photoluminescence and Raman spectroscopy signatures for identifying highly crystalline WS ₂ monolayers produced by different growth methods McCreary, Amber; Berkdemir, Ayse; Wang, Junjie Journal of Materials Research, Vol. 31, Issue 7 https://doi.org/10.1557/jmr.2016.47	journal	March 2016
Effect of contaminations and surface preparation on the work function of single layer MoS ₂ Ochedowski, Oliver; Marinov, Kolyo; Scheuschner, Nils Beilstein Journal of Nanotechnology, Vol. 5 https://doi.org/10.3762/bjnano.5.32	journal	January 2014
Open Counter for Low Energy Electron Detection M. Uda, M. Uda Japanese Journal of Applied Physics, Vol. 24, Issue S4 https://doi.org/10.7567/JJAPS.24S4.284	journal	January 1985

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Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
band alignment
ionization energy
molybdenum disulfide
molybdenum selenide
photoemission electron microscopy
transition metal dichalcogenide
tungsten disulfide