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Title: Ultrafast time-resolved extreme ultraviolet (XUV) photoelectron spectroscopy of hole transfer in a Zn/n-GaP Schottky junction

Abstract

The addition of a metal overlayer to a semiconductor photocatalyst is a frequently used synthetic route to passivate the surface and, via the formation of a Schottky barrier, to enhance catalytic activity of the photocatalyst material. While it is known that Schottky junctions decrease recombination by charge separation, measurements of the depletion region dynamics have remained elusive. Here, we use ultrafast pump-probe transient photoelectron spectroscopy to measure material-specific dynamics of the Zn/n-GaP(100) system. Through photoemission measurements the Schottky barrier height is determined to be 2.1± 0.1eV at 10 monolayers of total Zn deposition. Transient photoemission measurements utilizing a 400 nm pump pulse show that, after excitation, holes are transferred from n-GaP(100) to the Zn overlayer within a few ps, as evidenced by shifts of the Zn 3d and Ga 3d core levels to higher binding energies. Within the timescale of the experiment (130 ps) no carrier recombination is observed in the junction. Furthermore, a long-lived surface photovoltage signal is observed at times >1 ms after photoexcitation. This work further exemplifies the potential of transient extreme ultraviolet photoelectron spectroscopy as a material-specific technique for the study of heterojunctions.

Authors:
 [1];  [2];  [3]
  1. Univ. of California, Berkeley, CA (United States); Purdue Univ., West Lafayette, IN (United States)
  2. Univ. of California, Berkeley, CA (United States)
  3. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES); US Air Force Office of Scientific Research (AFOSR)
OSTI Identifier:
1616966
Grant/Contract Number:  
AC02-05CH11231; FA9550-14-1-0154
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Structural Dynamics
Additional Journal Information:
Journal Volume: 5; Journal Issue: 5; Journal ID: ISSN 2329-7778
Publisher:
American Crystallographic Association/AIP
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Marsh, Brett M., Lamoureux, Bethany R., and Leone, Stephen R. Ultrafast time-resolved extreme ultraviolet (XUV) photoelectron spectroscopy of hole transfer in a Zn/n-GaP Schottky junction. United States: N. p., 2018. Web. doi:10.1063/1.5046776.
Marsh, Brett M., Lamoureux, Bethany R., & Leone, Stephen R. Ultrafast time-resolved extreme ultraviolet (XUV) photoelectron spectroscopy of hole transfer in a Zn/n-GaP Schottky junction. United States. doi:10.1063/1.5046776.
Marsh, Brett M., Lamoureux, Bethany R., and Leone, Stephen R. Mon . "Ultrafast time-resolved extreme ultraviolet (XUV) photoelectron spectroscopy of hole transfer in a Zn/n-GaP Schottky junction". United States. doi:10.1063/1.5046776. https://www.osti.gov/servlets/purl/1616966.
@article{osti_1616966,
title = {Ultrafast time-resolved extreme ultraviolet (XUV) photoelectron spectroscopy of hole transfer in a Zn/n-GaP Schottky junction},
author = {Marsh, Brett M. and Lamoureux, Bethany R. and Leone, Stephen R.},
abstractNote = {The addition of a metal overlayer to a semiconductor photocatalyst is a frequently used synthetic route to passivate the surface and, via the formation of a Schottky barrier, to enhance catalytic activity of the photocatalyst material. While it is known that Schottky junctions decrease recombination by charge separation, measurements of the depletion region dynamics have remained elusive. Here, we use ultrafast pump-probe transient photoelectron spectroscopy to measure material-specific dynamics of the Zn/n-GaP(100) system. Through photoemission measurements the Schottky barrier height is determined to be 2.1± 0.1eV at 10 monolayers of total Zn deposition. Transient photoemission measurements utilizing a 400 nm pump pulse show that, after excitation, holes are transferred from n-GaP(100) to the Zn overlayer within a few ps, as evidenced by shifts of the Zn 3d and Ga 3d core levels to higher binding energies. Within the timescale of the experiment (130 ps) no carrier recombination is observed in the junction. Furthermore, a long-lived surface photovoltage signal is observed at times >1 ms after photoexcitation. This work further exemplifies the potential of transient extreme ultraviolet photoelectron spectroscopy as a material-specific technique for the study of heterojunctions.},
doi = {10.1063/1.5046776},
journal = {Structural Dynamics},
issn = {2329-7778},
number = 5,
volume = 5,
place = {United States},
year = {2018},
month = {10}
}

Journal Article:
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Works referenced in this record:

Ultra-thin metal films for enhanced solar absorption
journal, November 2012


Intrinsic Optical Absorption of Gallium Phosphide between 2.33 and 3.12 eV
journal, August 1967

  • Dean, P. J.; Kaminsky, G.; Zetterstrom, R. B.
  • Journal of Applied Physics, Vol. 38, Issue 9
  • DOI: 10.1063/1.1710170

Time-resolved HAXPES using a microfocused XFEL beam: From vacuum space-charge effects to intrinsic charge-carrier recombination dynamics
journal, October 2016

  • Oloff, Lars-Philip; Chainani, Ashish; Matsunami, Masaharu
  • Scientific Reports, Vol. 6, Issue 1
  • DOI: 10.1038/srep35087

Calculated Valence-Band Densities of States and Photoemission Spectra of Diamond and Zinc-Blende Semiconductors
journal, September 1973


Pump laser-induced space-charge effects in HHG-driven time- and angle-resolved photoelectron spectroscopy
journal, June 2016

  • Oloff, L. -P.; Hanff, K.; Stange, A.
  • Journal of Applied Physics, Vol. 119, Issue 22
  • DOI: 10.1063/1.4953643

X-ray photoemission determination of the Schottky barrier height of metal contacts to n –GaN and p –GaN
journal, December 2002

  • Rickert, K. A.; Ellis, A. B.; Kim, Jong Kyu
  • Journal of Applied Physics, Vol. 92, Issue 11
  • DOI: 10.1063/1.1518129

Femtosecond time-resolved core-level photoelectron spectroscopy tracking surface photovoltage transients on p –GaAs
journal, December 2002


Surface photovoltage effects in photoemission from metal-GaP(110) interfaces: Importance for band bending evaluation
journal, April 1990


Note: Binding energy scale calibration of electron spectrometers for photoelectron spectroscopy using a single sample
journal, September 2011

  • Helander, M. G.; Greiner, M. T.; Wang, Z. B.
  • Review of Scientific Instruments, Vol. 82, Issue 9
  • DOI: 10.1063/1.3642659

Ultrafast time resolution in scanned probe microscopies: Surface photovoltage on Si(111)–(7×7)
journal, March 1991

  • Hamers, R. J.
  • Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 9, Issue 2
  • DOI: 10.1116/1.585559

Photo-Electrochemical Behaviors of Semiconductor Electrodes Coated with thin Metal Films
journal, August 1975

  • Nakato, Yoshihiro; Ohnishi, Toshihiro; Tsubomura, Hiroshi
  • Chemistry Letters, Vol. 4, Issue 8
  • DOI: 10.1246/cl.1975.883

Role of photocurrent in low-temperature photoemission studies of Schottky-barrier formation
journal, April 1990


Review on Synthesis and Characterization of Gallium Phosphide
journal, January 2014


Surface photovoltage and photoelectron spectra of GaP
journal, February 2007

  • Kumar, Shailendra; Phase, D. M.; Porwal, Sanjay
  • Solid State Communications, Vol. 141, Issue 5
  • DOI: 10.1016/j.ssc.2006.10.038

Charge dynamics at heterojunctions for PbS/ZnO colloidal quantum dot solar cells probed with time-resolved surface photovoltage spectroscopy
journal, February 2016

  • Spencer, B. F.; Leontiadou, M. A.; Clark, P. C. J.
  • Applied Physics Letters, Vol. 108, Issue 9
  • DOI: 10.1063/1.4943077

Time-resolved surface photovoltage measurements at n -type photovoltaic surfaces: Si(111) and ZnO(10 1 ¯ 0)
journal, November 2013

  • Spencer, Ben F.; Graham, Darren M.; Hardman, Samantha J. O.
  • Physical Review B, Vol. 88, Issue 19
  • DOI: 10.1103/PhysRevB.88.195301

Surfactant-Free, Large-Scale, Solution–Liquid–Solid Growth of Gallium Phosphide Nanowires and Their Use for Visible-Light-Driven Hydrogen Production from Water Reduction
journal, December 2011

  • Sun, Jianwei; Liu, Chong; Yang, Peidong
  • Journal of the American Chemical Society, Vol. 133, Issue 48
  • DOI: 10.1021/ja2083398

Amorphous TiO2 coatings stabilize Si, GaAs, and GaP photoanodes for efficient water oxidation
journal, May 2014


Electron propagation from a photo-excited surface: implications for time-resolved photoemission
journal, November 2013


Nonmetal to Metal Transition and Ultrafast Charge Carrier Dynamics of Zn Clusters on p-Si(100) by fs-XUV Photoemission Spectroscopy
journal, June 2018


Efficient water reduction with gallium phosphide nanowires
journal, July 2015

  • Standing, Anthony; Assali, Simone; Gao, Lu
  • Nature Communications, Vol. 6, Issue 1
  • DOI: 10.1038/ncomms8824

Surface photovoltage effects on p -GaAs (100) from core-level photoelectron spectroscopy using synchrotron radiation and a laser
journal, September 2001


Investigation of Optical Transmission in Thin Metal Films
journal, January 2012


The growth and properties of Al and AlN films on GaN(0001)–(1×1)
journal, January 1996

  • Bermudez, V. M.; Jung, T. M.; Doverspike, K.
  • Journal of Applied Physics, Vol. 79, Issue 1
  • DOI: 10.1063/1.360917

Solar Hydrogen Production Using Molecular Catalysts Immobilized on Gallium Phosphide (111)A and (111)B Polymer-Modified Photocathodes
journal, April 2016

  • Beiler, Anna M.; Khusnutdinova, Diana; Jacob, Samuel I.
  • ACS Applied Materials & Interfaces, Vol. 8, Issue 15
  • DOI: 10.1021/acsami.6b01557

Band Gap of Gallium Phosphide from 0 to 900°K and Light Emission from Diodes at High Temperatures
journal, July 1968


Observation of Diffusion and Tunneling Recombination of Dye-Photoinjected Electrons in Ultrathin TiO 2 Layers by Surface Photovoltage Transients
journal, August 2005

  • Mora-Seró, Iván; Dittrich, Thomas; Belaidi, Abdelhak
  • The Journal of Physical Chemistry B, Vol. 109, Issue 31
  • DOI: 10.1021/jp058128w

Measuring the Surface Photovoltage of a Schottky Barrier under Intense Light Conditions: Zn/p-Si(100) by Laser Time-Resolved Extreme Ultraviolet Photoelectron Spectroscopy
journal, September 2017

  • Marsh, Brett M.; Vaida, Mihai E.; Cushing, Scott K.
  • The Journal of Physical Chemistry C, Vol. 121, Issue 40
  • DOI: 10.1021/acs.jpcc.7b06406