Basic XPS Information Section

The Basic XPS Information Section provides fundamental XPS spectra, BE values, FWHM values, BE tables, overlays of key spectra, histograms and a table of XPS parameters.
The Advanced XPS Information Section is a collection of additional spectra, overlays of spectra, peak-fit advice, data collection guidance, material info,
common contaminants, degradation during analysis, auto-oxidation, gas capture study, valence band spectra, Auger spectra, and more.
Published literature references, and website links are summarized at the end of the advanced section.
→  Periodic Table – HomePage                    XPS Database of Polymers                   → Six (6) BE Tables


Palladium (Pd)

 

Palladium Nitrate – PdNO3 Palladium – Pdo Palladium Oxide – PdO

 

 

  Page Index
  • Expert Knowledge & Explanations


Palladium (Pdo) Metal

Peak-fits, BEs, FWHMs, and Peak Labels

  .
Palladium (Pdo) Metal
Pd (3d) Spectrum – raw spectrum
ion etched clean		 Palladium (Pdo) Metal
Pd (3d) Spectrum – Peak-fit 
w/o asymm
→  Periodic Table – HomePage  
Palladium (Pdo) Metal
Pd (3d) Spectrum – extended range 
 Palladium (Pdo) Metal
Peak-fit of Pd (3d) Spectrum (w asymm)
 

 
Palladium (Pdo) Metal
Pd (4s) Spectrum		 Palladium (Pdo) Metal
Pd (4p) Spectrum

 

Survey Spectrum of Palladium (Pdo) Metal
with Peaks Integrated, Assigned and Labelled

 

 

→  Periodic Table 

XPS Signals for Palladium (Pdo) Metal

Spin-Orbit Term,  BE (eV) Value, and Scofield σ for Aluminum Kα X-rays (1486 eV, 8.33 Ang)

Overlaps Spin-Orbit Term BE (eV) Value Scofield σ from 1486 eV X-rays IMFP (TPP-2M) in Å
  Pd (3s) 671 2.81 11.9
  Pd (3p1/2) 560  3.83 13.4
O (1s) overlaps Pd (3p3/2) 532 7.63 13.4
  Pd (3d3/2) 340.3 6.56 15.4
Ca (2p) & Au (4d) overlap Pd (3d5/2) 335.0 9.48 15.4
  Pd (4s) 87 0.598 17.8
Li (1s) overlaps Pd (4p) 51  1.88 18.2

σ:  abbreviation for the term Scofield Photoionization Cross-Section which are used with IMFP and TF to generate RSFs and atom% quantitation

Energy Loss Peaks

Auger Peaks

Energy Loss:  ~xx eV above peak max
Expected Bandgap for PdO: ~2 eV  (Appl Materials Interface, 2016 Jul 6;8(26):16997-7003)
Work Function for PdO:  xx eV

*Scofield Cross-Section (σ) for C (1s) = 1.0

→  Periodic Table 

 

Pd (4s) and (4p) Signals from Pdo Metal
Fresh exposed bulk produced by extensive Ar+ ion etching

Pd (4s) and (4p) Pd (4p)
   

 

 

Valence Band Spectrum from Palladium, Pdo Metal
 Fresh exposed bulk produced by extensive Ar+ ion etching

 

 

Plasmon Peaks from Pdo Metal
 Fresh exposed bulk produced by extensive Ar+ ion etching

Pd (3d) – Extended Range Spectrum Pd (3d) – Extended Range Spectrum – Vertically Zoomed
→  Periodic Table 

 

Pd (LMM) Auger Peaks from Pdo Metal
 Fresh exposed bulk produced by extensive Ar+ ion etching
Pdo Metal – main Auger peaks Pdo Metal – all Auger peaks
 

Features Observed

  • xx
  • xx
  • xx

→  Periodic Table 

 

Artefacts Caused by Argon Ion Etching

Palladium Carbide(s)

can form when ion etched Reactive Metal Surfaces capture
Residual UHV Gases (CO, H2O, CH4 etc)

Argon Trapped in Pdo

can form when Argon Ions are used
to removed surface contamination
 

 

Side-by-Side Comparison of
Pd Native Oxide & Palladium Oxide (PdO)
Peak-fits, BEs, FWHMs, and Peak Labels
Pd Native Oxide PdO
Pd (3d) from Pd Native Oxide
Flood Gun OFF
As-Measured, C (1s) at 285.3 eV 		 Pd (3d) from PdO – pressed pellet
Flood Gun ON, C (1s) referenced to 285.0 eV

 
→  Periodic Table 
   .
Pd Native Oxide PdO
C (1s) from Pd Native Oxide
As-Measured, C (1s) at 285.3 eV (Flood Gun OFF)

C (1s) from PdO – pressed pellet
Flood Gun ON, C (1s) referenced to 285.0 eV

 
→  Periodic Table 
  . 
Pd Native Oxide PdO
O (1s) from Pd Native Oxide
 Overlaps Pd (3p3/2)
As-Measured, C (1s) at 285.3 eV (Flood Gun OFF)

O (1s) from PdO – pressed pellet
Overlaps Pd (3p3/2)
Flood Gun ON, C (1s) referenced to 285.0 eV

 
→  Periodic Table

 
.
Pd metal PdO
Pd (LMM) Auger Peaks from Pd metal
 

Pd (LMM) Auger Peaks from PdO – pressed pellet
Flood Gun ON, C (1s) referenced to 285.0 eV
 

 


Survey Spectrum of Palladium (Pd) Native Oxide
with Peaks Integrated, Assigned and Labelled

→  Periodic Table 

 

 

Survey Spectrum of Palladium Oxide (PdO)
with Peaks Integrated, Assigned and Labelled


→  Periodic Table  

 

Overlays of Pd (3d) Spectra for:
Pd Native Oxide and PdO

Caution: BEs from Grounded Native Oxides can be Misleading if Flood Gun is ON

 Overlay of Pdo metal and Pd Native Oxide – Pd (3d)
Native Oxide C (1s) = 285.3  (Flood gun OFF)
  Overlay of Pdo metal and PdO – Pd (3d) 
Flood Gun ON, C (1s) referenced to 285.0 eV
Chemical Shift:  1.9 eV
 
→  Periodic Table  Copyright ©:  The XPS Library 

 

Overlay of Pd (3d)
Pdo Metal, Pd Native Oxide, & PdO

Features Observed

  • xx
  • xx
  • xx

→  Periodic Table 

 

Valence Band Spectra
Pdo, PdO 

Pdo
Ion etched clean		 PdO – pressed pellet
Flood Gun ON, C (1s) referenced to 285.0 eV

Overlay of Valence Band Spectra
for Pdo metal and PdO

Features Observed

  • xx
  • xx
  • xx

→  Periodic Table 

 

Palladium Minerals, Gemstones, and Chemical Compounds

 
Palladium Chloride – PdCl2  Rustenburgite – (Pt,Pd)3Sn Natural Palladium – Pdo Palladium on Charcoal – Catalyst

→  Periodic Table 

 

 

Six (6) Chemical State Tables of Pd (3d5/2) BEs

 

  • The XPS Library Spectra-Base
  • PHI Handbook
  • Thermo-Scientific Website
  • XPSfitting Website
  • Techdb Website
  • NIST Website

→  Periodic Table 

 

Notes of Caution when using Published BEs and BE Tables from Insulators and Conductors:

  • Accuracy of Published BEs
    • The accuracy depends on the calibration BEs used to calibrate the energy scale of the instrument.  Cu (2p3) BE can vary from 932.2 to 932.8 eV for old publications 
    • Different authors use different BEs for the C (1s) BE of the hydrocarbons found in adventitious carbon that appears on all materials and samples.  From 284.2 to 285.3 eV
    • The accuracy depends on when the authors last checked or adjusted their energy scale to produce the expected calibration BEs
  • Worldwide Differences in Energy Scale Calibrations
    • For various reasons authors still use older energy scale calibrations 
    • Some authors still adjust their energy scale so Cu (3d5/2) appears at 932.2 eV or 932.8 eV because this is what the maker taught them
    • This range causes BEs in the higher BE end to be larger than expected 
    • This variation increases significantly above 600 eV BE
  • Charge Compensation
    • Samples that behave as true insulators normally require the use of a charge neutralizer (electron flood gun with or without Ar+ ions) so that the measured chemical state spectra can be produced without peak-shape distortions or sloping tails on the low BE side of the peak envelop. 
    • Floating all samples (conductive, semi-conductive, and non-conductive) and always using the electron flood gun is considered to produce more reliable BEs and is recommended.
  • Charge Referencing Methods for Insulators
    • Charge referencing is a common method, but it can produce results that are less reliable.
    • When an electron flood gun is used, the BE scale will usually shift to lower BE values by 0.01 to 5.0 eV depending on your voltage setting. Normally, to correct for this flood gun induced shift, the BE of the hydrocarbon C (1s) peak maximum from adventitious carbon is used to correct for the charge induced shift.
    • The hydrocarbon peak is normally the largest peak at the lowest BE. 
    • Depending on your preference or training, the C (1s) BE assigned to this hydrocarbon peak varies from 284.8 to 285.0 eV.  Other BEs can be as low as 284.2 eV or as high as 285.3 eV
    • Native oxides that still show the pure metal can suffer differential charging that causes the C (1s) and the O (1s) and the Metal Oxide BE to be larger
    • When using the electron flood gun, the instrument operator should adjust the voltage and the XY position of the electron flood gun to produce peaks from a strong XPS signal (eg O (1s) or C (1s) having the most narrow FWHM and the lowest experimentally measured BE. 

→  Periodic Table 

Table #1

Pd (3d5/2) Chemical State BEs from:  “The XPS Library Spectra-Base”

C (1s) BE = 285.0 eV for TXL BEs
and C (1s) BE = 284.8 eV for NIST BEs

Element Atomic # Compound As-Measured by TXL or NIST Average BE Largest BE Hydrocarbon C (1s) BE  Source
Pd 46 Pd – element 335.1 eV   285.0 eV The XPS Library
Pd 46 Pd (N*26) 335.1 eV 335.8 eV 284.8 eV Avg BE – NIST
Pd 46 PdO (N*6) 335.6 eV 337.1 eV 284.8 eV Avg BE – NIST
Pd 46 PdV3 (N*4) 335.6 eV 336.5 eV 284.8 eV Avg BE – NIST
Pd 46 CePd3 (N*4) 335.8 eV 336.6 eV 284.8 eV Avg BE – NIST
Pd 46 PdO3 (N*3) 336.2 eV 337.7 eV 284.8 eV Avg BE – NIST
Pd 46 PdSi2 (N*2) 336.2 eV 336.8 eV 284.8 eV Avg BE – NIST
Pd 46 Pd-I2 (N*2) 336.4 eV   284.8 eV Avg BE – NIST
Pd 46 Pd-O 336.9 eV   285.0 eV The XPS Library
Pd 46 Pd2F6 (N*2) 337.3 eV 339.2 eV 284.8 eV Avg BE – NIST
Pd 46 Pd-F2 (N*2) 337.5 eV 337.7 eV 284.8 eV Avg BE – NIST
Pd 46 Pd-Cl2 (N*4) 337.7 eV 337.8 eV 284.8 eV Avg BE – NIST
Pd 46 Pd-O2 (N*1) 337.9 eV   284.8 eV Avg BE – NIST
Pd 46 K2PdCl4 (N*3) 338.2 eV   284.8 eV Avg BE – NIST
Pd 46 Pd-(OH)2     285.0 eV The XPS Library

Charge Referencing Notes

  • (N*number) identifies the number of NIST BEs that were averaged to produce the BE in the middle column.
  • The XPS Library uses Binding Energy Scale Calibration with Cu (3d5/2) BE = 932.62 eV and Au (4f7/2) BE = 83.98 eV.  BE (eV) Uncertainty Range:  +/- 0.2 eV
  • Charge Referencing of insulators is defined such that the Adventitious Hydrocarbon C (1s) BE (eV) = 285.0 eV.  NIST uses C (1s) BE = 284.8 eV 
  • Note:   Ion etching removes adventitious carbon, implants Ar (+), changes conductivity of surface, and degrades chemistry of various chemical states.
  • Note:  Ion Etching changes BE of C (1s) hydrocarbon peak.
  • TXL – abbreviation for: “The XPS Library” (https://xpslibrary.com).  NIST:  National Institute for Science and Technology (in USA)

→  Periodic Table 

Table #2

Pd (3d5/2) Chemical State BEs from:  “PHI Handbook”

C (1s) BE = 284.8 eV

→  Periodic Table 

Copyright ©:  Ulvac-PHI

Table #3

Pd (3d5/2) Chemical State BEs from:  “Thermo-Scientific” Website

C (1s) BE = 284.8 eV

Chemical state Binding energy (eV),
Pd (3d5/2)
Pd metal 335.0
Native oxide 336.7

→  Periodic Table 

Copyright ©:  Thermo Scientific 

Table #4

Pd (3d5/2) Chemical State BEs from:  “XPSfitting” Website

Chemical State BE Table derived by Averaging BEs in the NIST XPS database of BEs
C (1s) BE = 284.8 eV

→  Periodic Table 

Copyright ©:  Mark Beisinger

Table #5

Pd (3d5/2) Chemical State BEs from:  “Techdb.podzone.net” Website

 

XPS Spectra – Chemical Shift | Binding Energy
C (1s) BE = 284.6 eV

XPS(X線光電子分光法)スペクトル 化学状態 化学シフト ケミカルシフト

Element Level Compound B.E.(eV) min   max
Pd 3d5/2 Pd 335.3 ±0.2 335.1 ～ 335.4
Pd 3d5/2 Pd3Si 336.3 ±0.2 336.1 ～ 336.5
Pd 3d5/2 PdO 336.3 ±0.2 336.1 ～ 336.5
Pd 3d5/2 Pd2Si 336.8 ±0.3 336.5 ～ 337.0
Pd 3d5/2 Halides 337.1 ±0.7 336.4 ～ 337.8
Pd 3d5/2 K2PdBr4 337.3 ±0.3 337.0 ～ 337.6
Pd 3d5/2 Pd(SPh)2 337.8 ±0.3 337.5 ～ 338.0
Pd 3d5/2 PdO2 338.0 ±0.3 337.7 ～ 338.2
Pd 3d5/2 K2PdCl4 338.4 ±0.3 338.1 ～ 338.6
Pd 3d5/2 Pd(OAc)2 338.7 ±0.3 338.4 ～ 338.9
Pd 3d5/2 K2PdCl6 340.3 ±0.3 340.0 ～ 340.5

 

→  Periodic Table 

 

 

Histograms of NIST BEs for Pd (3d5/2) BEs

Important Note:  NIST Database defines Adventitious Hydrocarbon C (1s) BE = 284.8 eV for all insulators.

Histogram indicates:  335.2 eV for Pdo based on 28 literature BEs Histogram indicates:  336.4 eV for PdO based on 8 literature BEs

Histogram indicates:  342.9 eV for PdF2 based on 2 literature BEs

Table #6


NIST Database of Pd (3d5/2) Binding Energies

NIST Standard Reference Database 20, Version 4.1

Data compiled and evaluated
by
Alexander V. Naumkin, Anna Kraut-Vass, Stephen W. Gaarenstroom, and Cedric J. Powell
©2012 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Important Note:  NIST Database defines Adventitious Hydrocarbon C (1s) BE = 284.8 eV for all insulators.

Element Spectral Line Formula Energy (eV) Reference
Pd 3d5/2 Pd 334.10  Click
Pd 3d5/2 Pd 334.10  Click
Pd 3d5/2 Pd/SiOx/Si 334.40  Click
Pd 3d5/2 Pd/Al2O3 334.75  Click
Pd 3d5/2 Pd/SiOx/Si 334.90  Click
Pd 3d5/2 Pd 335.00  Click
Pd 3d5/2 Pd 335.00  Click
Pd 3d5/2 Pd 335.00  Click
Pd 3d5/2 Pd/Pt 335.00  Click
Pd 3d5/2 Pd 335.08  Click
Pd 3d5/2 Pd 335.08  Click
Pd 3d5/2 Pd 335.10  Click
Pd 3d5/2 Pd 335.10  Click
Pd 3d5/2 Pd 335.10  Click
Pd 3d5/2 Pd 335.10  Click
Pd 3d5/2 Pd 335.10  Click
Pd 3d5/2 PdOx/Pd 335.10  Click
Pd 3d5/2 PdOx/Pd 335.10  Click
Pd 3d5/2 PdH0.60/Ba 335.10  Click
Pd 3d5/2 Pd/Au 335.10  Click
Pd 3d5/2 Pd 335.18  Click
Pd 3d5/2 Pd 335.19  Click
Pd 3d5/2 PdO 335.20  Click
Pd 3d5/2 Pd 335.20  Click
Pd 3d5/2 Pd 335.20  Click
Pd 3d5/2 Pd 335.20  Click
Pd 3d5/2 Pd 335.20  Click
Pd 3d5/2 Pd 335.20  Click
Pd 3d5/2 Pd 335.20  Click
Pd 3d5/2 Pd 335.20  Click
Pd 3d5/2 Pd 335.20  Click
Pd 3d5/2 Pd/Al2O3 335.20  Click
Pd 3d5/2 Pd(P(C6H5)3)4 335.20  Click
Pd 3d5/2 Pd49Ag51/C 335.20  Click
Pd 3d5/2 Pd/Pt 335.20  Click
Pd 3d5/2 CePd3 335.25  Click
Pd 3d5/2 Pd 335.30  Click
Pd 3d5/2 Pd 335.30  Click
Pd 3d5/2 EuPd3 335.30  Click
Pd 3d5/2 EuPd5 335.30  Click
Pd 3d5/2 Pd/Au 335.30  Click
Pd 3d5/2 Pd/Au 335.30  Click
Pd 3d5/2 Pd/Au 335.30  Click
Pd 3d5/2 Pd/Au 335.30  Click
Pd 3d5/2 Pd 335.35  Click
Pd 3d5/2 Pd60Ag40/C 335.35  Click
Pd 3d5/2 Eu/Pd 335.37  Click
Pd 3d5/2 Pd 335.40  Click
Pd 3d5/2 Pd 335.40  Click
Pd 3d5/2 Pd65Ag35/C 335.40  Click
Pd 3d5/2 Eu/Pd 335.40  Click
Pd 3d5/2 Pd/Pt 335.40  Click
Pd 3d5/2 Pd 335.42  Click
Pd 3d5/2 Al10Pd90 335.45  Click
Pd 3d5/2 Pd 335.47  Click
Pd 3d5/2 Eu/Pd 335.47  Click
Pd 3d5/2 Pd 335.50  Click
Pd 3d5/2 Pd 335.50  Click
Pd 3d5/2 Pd/C 335.50  Click
Pd 3d5/2 Pd3Y2 335.55  Click
Pd 3d5/2 PdO 335.60  Click
Pd 3d5/2 Pd 335.60  Click
Pd 3d5/2 Pd 335.60  Click
Pd 3d5/2 Pd 335.60  Click
Pd 3d5/2 PdV3 335.60  Click
Pd 3d5/2 Pd/C 335.60  Click
Pd 3d5/2 Pd/C 335.60  Click
Pd 3d5/2 Ag24.5Pd75.5 335.60  Click
Pd 3d5/2 Ag25.9Pd74.1 335.60  Click
Pd 3d5/2 NiPd 335.65  Click
Pd 3d5/2 Pd 335.70  Click
Pd 3d5/2 Pd 335.70  Click
Pd 3d5/2 Pd3Pr 335.70  Click
Pd 3d5/2 LaPd2 335.75  Click
Pd 3d5/2 EuPd2 335.77  Click
Pd 3d5/2 Pd 335.80  Click
Pd 3d5/2 NdPd3 335.80  Click
Pd 3d5/2 Pd3Sm 335.80  Click
Pd 3d5/2 Pd3Ti 335.80  Click
Pd 3d5/2 Eu/Pd 335.80  Click
Pd 3d5/2 CePd3 335.85  Click
Pd 3d5/2 EuPd 335.87  Click
Pd 3d5/2 PdO 335.90  Click
Pd 3d5/2 Eu/Pd 335.90  Click
Pd 3d5/2 PdO 335.90  Click
Pd 3d5/2 [Pd((C6H5)3P)4] 336.00  Click
Pd 3d5/2 Pd2Ta 336.00  Click
Pd 3d5/2 Pd/C 336.00  Click
Pd 3d5/2 NbPd2 336.10  Click
Pd 3d5/2 LaPd2 336.10  Click
Pd 3d5/2 PdV3 336.10  Click
Pd 3d5/2 PdV3 336.10  Click
Pd 3d5/2 CePd3 336.20  Click
Pd 3d5/2 Pd2Si 336.20  Click
Pd 3d5/2 PdO3 336.20  Click
Pd 3d5/2 C60Pd4.9 336.20  Click
Pd 3d5/2 Pd3Th 336.25  Click
Pd 3d5/2 PdO 336.30  Click
Pd 3d5/2 Pd2Ta 336.30  Click
Pd 3d5/2 Pd3U 336.30  Click
Pd 3d5/2 Pd85Ag15/C 336.30  Click
Pd 3d5/2 Pd/C 336.30  Click
Pd 3d5/2 Pd/C 336.30  Click
Pd 3d5/2 PdSc 336.35  Click
Pd 3d5/2 LaPd2 336.40  Click
Pd 3d5/2 PdI2 336.40  Click
Pd 3d5/2 PdOx/Pd 336.40  Click
Pd 3d5/2 Pd/C 336.40  Click
Pd 3d5/2 C60Pd2.9 336.40  Click
Pd 3d5/2 Pd2(dba)3.CHCl3 336.40  Click
Pd 3d5/2 Pd90Ag10/C 336.45  Click
Pd 3d5/2 Pd2Ta 336.50  Click
Pd 3d5/2 PdV3 336.50  Click
Pd 3d5/2 PdH0.60/Ba 336.50  Click
Pd 3d5/2 C60Pd1.0 336.50  Click
Pd 3d5/2 CePdAl 336.55  Click
Pd 3d5/2 LaPd2 336.55  Click
Pd 3d5/2 [Pd2(P(C6H5)3)2] 336.60  Click
Pd 3d5/2 LaPdAl 336.60  Click
Pd 3d5/2 CePd3 336.60  Click
Pd 3d5/2 Pd3Th 336.60  Click
Pd 3d5/2 PdOx/Pd 336.60  Click
Pd 3d5/2 ((CH3)2(CH3(CH2)17)2N)Pt(Cl)6/SiO2 336.60  Click
Pd 3d5/2 Pd3Th 336.70  Click
Pd 3d5/2 [(CH3)2CHC6H4CH=CHC(O)CH=CHC6H4CH(CH3)2]3Pd/ZnSe 336.70  Click
Pd 3d5/2 ThPdAl 336.75  Click
Pd 3d5/2 Pd3Y2 336.75  Click
Pd 3d5/2 [Pd2(SP(C6H5)2)2(P(C6H5)3)2] 336.80  Click
Pd 3d5/2 Pd2Si 336.80  Click
Pd 3d5/2 [Pd2(CH3COO)2(P(C6H5)3)2] 336.90  Click
Pd 3d5/2 [N(C2H5)4][Pd((C6H5)C(S)C(S)(C6H5))2] 336.90  Click
Pd 3d5/2 PdO 336.90  Click
Pd 3d5/2 K2[Pd(NCS)4] 337.00  Click
Pd 3d5/2 PdO 337.00  Click
Pd 3d5/2 Pd/SnO2 337.00  Click
Pd 3d5/2 Pd/Al 337.00  Click
Pd 3d5/2 Al3Pd 337.05  Click
Pd 3d5/2 [Pd(P(C6H5)3)2(SeP(C6H5)2)2] 337.10  Click
Pd 3d5/2 PdBr2 337.10  Click
Pd 3d5/2 [Pd2Cl2((C6H5)2PCH2P(C6H5)2)2] 337.10  Click
Pd 3d5/2 PdO 337.10  Click
Pd 3d5/2 PdO 337.10  Click
Pd 3d5/2 Pd/CeO2 337.10  Click
Pd 3d5/2 Al56Mn8Pd36 337.10  Click
Pd 3d5/2 Al56Mn8Pd36 337.10  Click
Pd 3d5/2 [(Pt2(P(C6H5)3)4S2Pd)2Cl2][PF6]2 337.10  Click
Pd 3d5/2 [PdCl2((C6H5)2AsCH2As(C6H5)2)2] 337.20  Click
Pd 3d5/2 PdO 337.20  Click
Pd 3d5/2 (N(H)-C(CH3)=C(CN)-C(S)-S-CH2-C(O)-O-C2H5)2Pd 337.20  Click
Pd 3d5/2 (C6H4S4)2[Pd(S2C2O2)2] 337.20  Click
Pd 3d5/2 Pd/CeO2/Al2O3 337.20  Click
Pd 3d5/2 Pd/CeO2/Al2O3 337.20  Click
Pd 3d5/2 Pd/Al2O3 337.20  Click
Pd 3d5/2 K2PdBr4 337.30  Click
Pd 3d5/2 Pd2F6 337.30  Click
Pd 3d5/2 Pd/CeO2/Al2O3 337.30  Click
Pd 3d5/2 Pd/Al2O3 337.30  Click
Pd 3d5/2 Al70Mn9Pd21 337.30  Click
Pd 3d5/2 Al70Mn9Pd21 337.30  Click
Pd 3d5/2 Al72.1Mn6.9Pd21.0Ox 337.30  Click
Pd 3d5/2 Al70.5Mn6.4Pd23.1 337.30  Click
Pd 3d5/2 Al78.9Mn3.8Pd17.3Ox 337.30  Click
Pd 3d5/2 [Pd(C6H5Br)(P(C6H5)3)2] 337.40  Click
Pd 3d5/2 [Pd((C6H5)CSSC(C6H5))2] 337.40  Click
Pd 3d5/2 [Pd2SCl2((C6H5)2PCH2P(C6H5)2)2] 337.40  Click
Pd 3d5/2 [PdI2(P(C6H5)3)2] 337.50  Click
Pd 3d5/2 PdF2 337.50  Click
Pd 3d5/2 RbPdF3 337.50  Click
Pd 3d5/2 Pd(S2CNHCH(CH2CH(CH3)2)COOH)2 337.50  Click
Pd 3d5/2 PdO2 337.50  Click
Pd 3d5/2 PdO3 337.60  Click
Pd 3d5/2 Al3Pd 337.70  Click
Pd 3d5/2 PdCl2 337.70  Click
Pd 3d5/2 [Pd(-C-6H5S)2] 337.70  Click
Pd 3d5/2 [PdCl2((C6H5)3P)2] 337.70  Click
Pd 3d5/2 [Pd2(SO2)Cl2((C6H5)2PCH2P(C6H5)2)2] 337.70  Click
Pd 3d5/2 K2PdBr4 337.70  Click
Pd 3d5/2 PdO3 337.70  Click
Pd 3d5/2 PdF2 337.70  Click
Pd 3d5/2 [PdBr2(P(C6H5)3)2] 337.80  Click
Pd 3d5/2 [PdBr2(P(C6H5)3)2] 337.80  Click
Pd 3d5/2 [Pd(SC(SCH3)CHC(C6H5)O)2] 337.80  Click
Pd 3d5/2 PdCl2 337.80  Click
Pd 3d5/2 PdCl2 337.80  Click
Pd 3d5/2 PdCl2 337.80  Click
Pd 3d5/2 [Pd2(NCCH3)6]PF6 337.80  Click
Pd 3d5/2 [PdCl2((C6H5)3P)2] 337.80  Click
Pd 3d5/2 [PdCl2((C6H5)3P)2] 337.80  Click
Pd 3d5/2 PdCl2 337.80  Click
Pd 3d5/2 Na3PdF6 337.80  Click
Pd 3d5/2 (N(C6H5)-C(CH3)=C(CN)-C(S)-S-CH2-C(O)-O-C2H5)2)Pd 337.80  Click
Pd 3d5/2 [((C6H5)2P(CH2)3P(C6H5)2)PdCl2] 337.80  Click
Pd 3d5/2 [Pd(HCOO)2(P(C6H5)3)2] 337.90  Click
Pd 3d5/2 [Pd(SCN)4(P(C6H5)4)2] 337.90  Click
Pd 3d5/2 [Pd(CH3COO)2((C6H5)3P)2] 337.90  Click
Pd 3d5/2 PdO2 337.90  Click
Pd 3d5/2 (N(H)-C(C6H5)=C(CN)-C(S)-S-C2H5)2Pd 337.90  Click
Pd 3d5/2 Pd(C12H8N2)(CH3C(O)O)2/(-CH-CH2-(C6H5))n 337.90  Click
Pd 3d5/2 [PdCO3(P(C6H5)3)2] 338.00  Click
Pd 3d5/2 [PdCl2((C6H5)3P)2] 338.00  Click
Pd 3d5/2 [PdBr2((NH2)C3NO(CH3)2)] 338.00  Click
Pd 3d5/2 Na2PdCl4 338.00  Click
Pd 3d5/2 K2NaPdF6 338.00  Click
Pd 3d5/2 PdCl2 338.00  Click
Pd 3d5/2 PdCl2 338.00  Click
Pd 3d5/2 K3PdF6 338.00  Click
Pd 3d5/2 [PdCl2(C6H5P(C2H5)2)2] 338.10  Click
Pd 3d5/2 [PdBr2(C6H5CN)2] 338.10  Click
Pd 3d5/2 [PdCl2(C6H5P(C2H5)2)2] 338.10  Click
Pd 3d5/2 [PdCl2(C5H5N)2] 338.10  Click
Pd 3d5/2 Pd(P(C6H5)3)2Cl2 338.10  Click
Pd 3d5/2 Pd[C&=CSi(CH3)3]2(P(C6H5)3)2 338.10  Click
Pd 3d5/2 [Pd(CN)2(P(C6H5)3)2] 338.20  Click
Pd 3d5/2 [PdBr2(C3H3NO)2] 338.20  Click
Pd 3d5/2 K2PdCl4 338.20  Click
Pd 3d5/2 K2PdCl4 338.20  Click
Pd 3d5/2 K2PdCl4 338.20  Click
Pd 3d5/2 [PdCl2((NH2)C3NO(CH3)2)] 338.20  Click
Pd 3d5/2 [PdCl2(C5H5N)2] 338.30  Click
Pd 3d5/2 [PdCl2(C3H3NO)2] 338.40  Click
Pd 3d5/2 [PdCl2(CH2(NH2)CH2(NH2))2] 338.40  Click
Pd 3d5/2 [PtCl2((NH2)2CHCH3)2][Pd((NH2)2CHCH3)2](ClO4)4 338.40  Click
Pd 3d5/2 [PdBr2(C3HNO(CH3)2)] 338.40  Click
Pd 3d5/2 [PdCl2(CH3(C3HNO)CH3)2] 338.40  Click
Pd 3d5/2 [PdBr2((CH3)C3HNO(C6H5))2] 338.40  Click
Pd 3d5/2 [Pd(NH3)2]Br2 338.40  Click
Pd 3d5/2 PdCl2 338.40  Click
Pd 3d5/2 Pd(CH3-(C5H3N)-N=N-(C6H3)(O)(OH))Cl.H2O 338.40  Click
Pd 3d5/2 [((C6H5)2P(CH2)3P(C6H5)2)2Pd](CF3COO)2 338.40  Click
Pd 3d5/2 [PdCl2(C6H5CH2CN)2] 338.50  Click
Pd 3d5/2 [PdCl2((CH3)C3HNO(C6H5))2] 338.50  Click
Pd 3d5/2 [Pd(H2NC2H4NH2)2][PtBr2(H2NC2H4NH2)2](ClO4)4 338.50  Click
Pd 3d5/2 [Pd(NH3)2]Cl2 338.50  Click
Pd 3d5/2 [Pd(H2NC2H4NH2)2][PdCl2(H2NC2H4NH2)2](ClO4)4 338.55  Click
Pd 3d5/2 [PdCl2C6H10] 338.60  Click
Pd 3d5/2 [PdCl2(C6H5CN)2] 338.60  Click
Pd 3d5/2 Pd(C2H3O2)2 338.60  Click
Pd 3d5/2 Pd(CF3COO)2 338.60  Click
Pd 3d5/2 [PtI2((NH2)2CHCH3)2][Pd((NH2)2CHCH3)2](ClO4)4 338.70  Click
Pd 3d5/2 Pd(NH3)4Cl2 338.70  Click
Pd 3d5/2 [PdI2(CH3CN)2] 338.70  Click
Pd 3d5/2 [Pd(NH2)2Cl2].2H2O 338.70  Click
Pd 3d5/2 [Pd(H2NC2H4NH2)2][PdBr2(H2NC2H4NH2)2](ClO4)4 338.74  Click
Pd 3d5/2 [PdBr2(P(C6H5O)3)2] 338.80  Click
Pd 3d5/2 Pd(C2H3O2)2 338.80  Click
Pd 3d5/2 K2[Pd(NO2)4] 338.80  Click
Pd 3d5/2 K2[Pd(NO2)4] 339.00  Click
Pd 3d5/2 [Pd(NH3)2(NO2)2] 339.10  Click
Pd 3d5/2 Pd2F6 339.20  Click
Pd 3d5/2 [Pd(CH3CN)4](PF6)2 339.30  Click
Pd 3d5/2 K2[PdCl6] 340.10  Click
Pd 3d5/2 Pd(NH3)4Cl2 340.10  Click
Pd 3d5/2 K2[PdCl6] 340.30  Click
Pd 3d5/2 K2[PdCl6] 340.30  Click
Pd 3d5/2 [Pd(H2NC2H4NH2)2][PdBr2(H2NC2H4NH2)2](ClO4)4 340.34  Click
Pd 3d5/2 [Pd(H2NC2H4NH2)2][PdCl2(H2NC2H4NH2)2](ClO4)4 340.44  Click
Pd 3d5/2 Pd2F6 342.70  Click
Pd 3d5/2 [PdCl2(P(C6H5)3)3] 342.90  Click

 

 

Statistical Analysis of Binding Energies in NIST XPS Database of BEs

 

 

→  Periodic Table 

 

Advanced XPS Information Section

Expert Knowledge, Spectra, Features, Guidance and Cautions
for XPS Research Studies on Palladium Materials

 

 

Expert Knowledge Explanations

→  Periodic Table 

 

Palladium Chemical Compounds


Peak-fits and Overlays of Chemical State Spectra

Pure Palladium, Pdo:  Pd (3d)
Cu (2p3/2) BE = 932.6 eV		 PdO:  Pd (3d)
C (1s) BE = 285.0 eV		 PdF2: Pd (3d)
C (1s) BE = 285.0 eV
 

Features Observed

  • xx
  • xx
  • xx

→  Periodic Table 

 

Palladium Oxide (PdO)
pressed pellet

Survey Spectrum from PdO
Flood Gun ON, C (1s) referenced to 285.0 eV		 Pd (3d) Chemical State Spectrum from PdO
Flood Gun ON, C (1s) referenced to 285.0 eV
  . 
O (1s) Chemical State Spectrum from PdO
Flood Gun ON, C (1s) referenced to 285.0 eV		 C (1s) Chemical State Spectrum from PdO
Flood Gun ON, C (1s) referenced to 285.0 eV
  . 
Valence Band Spectrum from PdO
Flood Gun ON, C (1s) referenced to 285.0 eV		 Auger Signals from PdO
Flood Gun ON, C (1s) referenced to 285.0 eV


Shake-up Features for
PdO

Pdo metal PdO

 

 

Multiplet Splitting Features
for Palladium Compounds

Pd metal – NO Splitting for Pd (4s and 4p) PdO – NO Splitting for Pd (4s and 4p)

 

 

Features Observed

  • xx
  • xx
  • xx

→  Periodic Table 

 

 

Palladium Chemical Compounds

   
   
   

→  Periodic Table 

 

Quantitation Details and Information

Quantitation by XPS is often incorrectly done, in many laboratories, by integrating only the main peak, ignoring the Electron Loss peak, and the satellites that appear as much as 30 eV above the main peak.  By ignoring the electron loss peak and the satellites, the accuracy of the atom% quantitation is in error.

When using theoretically calculated Scofield cross-section values, the data must be corrected for the transmission function effect, use the calculated TPP-2M IMFP values, the pass energy effect on the transmission function, and the peak area used for calculation must include the electron loss peak area, shake-up peak area, multiplet-splitting peak area, and satellites that occur within 30 eV of the main peak.

 

Quantitation from Pure, Homogeneous Binary Compound
composed of Palladium – PdO

This section is focused on measuring and reporting the atom % quantitation that results by using:

  • Scofield cross-sections,
  • Spectra corrected to be free from Transmission Function effects
  • A Pass Energy that does not saturate the detector system in the low KE range (BE = 1000-1400 eV)
  • A focused beam of X-ray smaller than the field of view of the lens
  • An angle between the lens and the source that is ~55 deg that negates the effects of beta-asymmetry
  • TPP-2M inelastic mean free path values, and
  • Either a linear background or an iterated Shirley (Sherwood-Proctor) background to define peak areas

The results show here are examples of a method being developed that is expected to improve the “accuracy” or “reliability” of the atom % values produced by XPS.

→  Periodic Table 

 

 

 

Flood Gun Effect on Native Oxide of Palladium

 

Native Oxide of Palladium Sheet – Sample GROUNDED

 

 

Native Oxide of Palladium Sheet – Sample Grounded

Electron Flood Gun:  0 Voltage (FG OFF), Min Voltage versus Max Voltage

Pd (3d) O (1s) C (1s)
     
→  Periodic Table     

 

XPS Study of UHV Gas Captured by Freshly Ion Etched Palladium
 
Reveals Chemical Shifts and Chemical States that Develop from Highly Reactive Pure Pdo

Surface was strongly Ar+ ion etched to remove all contaminants, and
then allowed to react overnight with the UHV Gases – CO, H2, H2O, O2 & CH4
that normally reside inside on the walls of the chamber, on the sample stage,
and on the nearby un-etched surface a total of 10-14 hours.  UHV pump was a Cryopump.
Initial spectra are at the front.  Final spectra are at the rear. Flood gun is OFF.
 
 
 
Pd (3d) Signal
  O (1s) Signal C (1s) Signal
     
 
Copyright ©:  The XPS Library
 

 

Auger Chemical State Spectra from Overnight UHV Gas Capture (14 hr) by AES

Palladium sheet was ion etched and allowed to react with residual UHV gases overnight – ~14 hr run.

Pd (LMM) Signal:
Pd at front -> PdX at rear 
Pd KE = 323.6 eV		 O (KLL) Signal:
Pd at front -> PdX at rear 
O KE = XXXX eV		 C (KLL) Signal:
Pd at front -> PdX at rear 
O KE = 271.5 eV
 

Features Observed

  • xx
  • xx
  • xx

→  Periodic Table 

 

 

Palladium Alloys

   
XxCu XxCu
→  Periodic Table   
XxCu XxCu

 

Copyright ©:  The XPS Library 

 

 

XPS Facts, Guidance & Information

→  Periodic Table 

    Element   Palladium (Pd)
  
    Primary XPS peak used for Peak-fitting:   Pd (3d)  
    Spin-Orbit (S-O) splitting for Primary Peak:   Spin-Orbit splitting for “d” orbital, ΔBE = 5.2 eV
  
    Binding Energy (BE) of Primary XPS Signal:   335 eV
  
    Scofield Cross-Section (σ) Value:   Pd (3d5/2) = 9.48      Pd (3d3/2) = 6.56
  
    Conductivity:   Pd resistivity =  
Native Oxide suffers Differential Charing		  
    Range of Pd (3d5/2) Chemical State BEs:   335 – 338 eV range   (Pdo to PdF2)  
    Signals from other elements that overlap
Pd (3d5/2) Primary Peak:		   xx (xx)  
    Bulk Plasmons:   ~xx eV above peak max for pure  
    Shake-up Peaks:   xx  
    Multiplet Splitting Peaks:   xx  

 

 

 General Information about
XXX Compounds:		   xx  
    Cautions – Chemical Poison Warning  

xx 

  

Copyright ©:  The XPS Library 

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Information Useful for Peak-fitting Pd (3d5/2)

  • FWHM (eV) of Pd (3d5/2) for Pure Pdo :  ~0.77 eV using 25 eV Pass Energy after ion etching:
  • FWHM (eV) of Pd (3d5/2) for PdO:  ~1.0 eV using 50 eV Pass Energy  (before ion etching)
  • Binding Energy (BE) of Primary Signal used for Measuring Chemical State Spectra:  335 eV for Pd (3d5/2) with +/- 0.2 uncertainty
  • List of XPS Peaks that can Overlap Peak-fit results for Pd (3d5/2):  xxxx

→  Periodic Table 

 

General Guidelines for Peak-fitting XPS Signals

  • Typical Energy Resolution for Pass Energy (PE) setting used to measure Chemical State Spectra on Various XPS Instruments
    • Ag (3d5/2) FWHM (eV) = ~0.95 eV for PE 50 on Thermo K-Alpha
    • Ag (3d5/2) FWHM (eV) = ~1.00 eV for PE 80 on Kratos Nova
    • Ag (3d5/2) FWHM (eV) = ~0.95 eV for PE 45 on PHI VersaProbe
  • FWHM (eV) of Pure Elements: Ranges from 0.4 to 1.0 eV across the periodic table
  • FWHM of Chemical State Peaks in any Chemical Compound:  Ranges from 1.1 to 1.6 eV  (in rare cases FWHM can be 1.8 to 2.0 eV)
  • FWHM of Pure Element versus FWHM of Oxide:  Pure element FWHM << Oxide FWHM  (e.g. 0.8 vs 1.5 eV, roughly 2x)
  • If FWHM Greater than 1.6 eV:  When a peak FWHM is larger than 1.6 eV, it is best to add another peak to the peak-fit envelop.
  • BE (eV) Difference in Chemical States: The difference in chemical state BEs is typically 1.0-1.3 eV apart.  In rare cases, <0.8 eV.
  • Number of Peaks to Use:  Use minimum. Do not use peaks with FWHM < 1.0 eV unless it is a or a conductive compound.
  • Typical Peak-Shape:  80% G: 20% L,   or Voigt : 1.4 eV Gaussian and 0.5 eV Lorentzian
  • Spin-Orbit Splitting of Two Peaks (due to Coupling):  The ratio of the two (2) peak areas must be constrained.

Notes:

  • Other Oxidation States can appear as small peaks when peak-fitting
  • Pure element signals normally have asymmetric tails that should be included in the peak-fit.
  • Gaseous state materials often display asymmetric tails due to vibrational broadening.
  • Peak-fits of C (1s) in polymers include an asymmetric tail when the energy resolution is very high.
  • Binding energy shifts of some compounds are negative due to unusual electron polarization.

→  Periodic Table 

 

Contaminants Specific to Palladium

  • Palladium develops a thick native oxide due to the reactive nature of clean Palladium.
  • The native oxide of Pd Ox is 1-2 nm thick.
  • Palladium thin films often have a low level of iron (Fe) in the bulk as a contaminant or to strengthen the thin film
  • Palladium forms a low level of carbide when the surface is ion etched inside the analysis chamber

 

Commonplace Contaminants

  • Carbon and Oxygen are common contaminants that appear on nearly all surfaces. The amount of Carbon usually depends on handling.
  • Carbon is usually the major contaminant.  The amount of carbon ranges from 5-50 atom%.
  • Carbon contamination is attributed to air-borne organic gases that become trapped by the surface, oils transferred to the surface from packaging containers, static electricity, or handling of the product in the production environment.
  • Carbon contamination is normally a mixture of different chemical states of carbon (hydrocarbon, alcohol or ether, and ester or acid).
  • Hydrocarbon is the dominant form of carbon contamination. It is normally 2-4x larger than the other chemical states of carbon.
  • Carbonate peaks, if they appear, normally appear ~4.5 eV above the hydrocarbon C (1s) peak max BE.
  • Low levels of carbonate is common on many s that readily oxidize in the air.
  • High levels of carbonate appear on reactive oxides and various hydroxides.  This is due to reaction between the oxide and CO2 in the air.
  • Hydroxide contamination peak is due to the reaction with residual water in the lab air or the vacuum.
  • The O (1s) BE of the hydroxide (water) contamination normally appears 0.5 to 1.0 eV above the oxide peak
  • Sodium (Na), Potassium (K), Sulfur (S) and Chlorine (Cl) are common trace to low level contaminants
  • To find low level contaminants it is very useful to vertically expand the 0-600 eV region of the survey spectrum by 5-10X
  • A tiny peak that has 3 or more adjacent data-points above the average noise of the background is considerate to be a real peak
  • Carbides can appear after ion etching various reactive s.  Carbides form due to the residual CO and CH4 in the vacuum.
  • Ion etching can produce low oxidation states of the material being analyzed.  These are newly formed contaminants.
  • Ion etching polymers by using standard Ar+ ion guns will destroy the polymer, converting it into a graphitic type of carbon

→  Periodic Table 

 

Data Collection Guidance

  • Chemical state differentiation can be difficult
  • Collect principal Pd (3d) peak as well as Pd (3p).
  • Long time exposures (high dose) to X-rays can degrade various polymers, catalysts, high oxidation state compounds
  • During XPS analysis, water or solvents can be lost due to high vacuum or irradiation with X-rays or Electron flood gun
  • Auger signals can sometimes be used to discern chemical state shifts when XPS shifts are very small

→  Periodic Table 

 

Data Collection Settings for Palladium (Pd)

  • Conductivity:  Palladium readily develops a native oxide that is sensitive to Flood Gun – Differential Charging Possible – float sample recommended
  • Primary Peak (XPS Signal) used to measure Chemical State Spectra:  Pd (3d5/2) at 335 eV
  • Recommended Pass Energy for Measuring Chemical State Spectrum:  40-50 eV    (Produces Ag (3d5/2) FWHM ~0.7 eV)
  • Recommended # of Scans for Measuring Chemical State Spectrum:  4-5 scans normally   (Use 10-25 scans to improve S/N)
  • Dwell Time:  50 msec/point
  • Step Size:  0.1 eV/point   (0.1 eV/step or 0.1 eV/channel)
  • Standard BE Range for Measuring Chemical State Spectrum:  325 – 355 eV
  • Recommended Extended BE Range for Measuring Chemical State Spectrum:  320-420 eV
  • Recommended BE Range for Survey Spectrum:  -10 to 1,100 eV   (above 1,100 eV there are no useful XPS signals, except for Ge and Ga)
  • Typical Time for Survey Spectrum:  3-5 minutes for newer instruments, 5-10 minutes for older instruments
  • Typical Time for a single Chemical State Spectrum with high S/N:  5-10 minutes for newer instruments, 10-15 minutes for older instruments 

→  Periodic Table 

 

Effects of Argon Ion Etching

  • Carbides appear after ion etching Pd and various reactive surfaces.  Carbides form due to the presence of residual CO and CH4 in the vacuum.
  • Ion etching can produce low oxidation states of the material being analyzed.  These are newly formed contaminants.
  • Ion etching polymers by using standard Ar+ ion guns will destroy the polymer, converting it into a graphitic type of carbon

→  Periodic Table 

Copyright ©:  The XPS Library 
 
 
Gas Phase XPS or UPS Spectra
 
 
     
     
     
     
     
     
     
     
     
 
 
 
 

 

Chemical State Spectra from Literature
 
 
xxx
 

End of File