International Business Environments and Operations 16th Global Edition test b...
Chem Analysis
1. Materials Characterization Lab
www.mri.psu.edu/mcl
Elemental Analyses by ICP-AES/ICP-MS
Henry Gong, Senior Analytical Chemist
John Kittleson, ICP Mass Spectroscopist
July 27, 2005
2. Materials Characterization Lab
www.mri.psu.edu/mcl
Summer Characterization Open Houses
Technique Time Date Location
Thermal analysis (TGA, DTA, DSC) 9:45 AM June 8 250 MRL Bldg.
Transmission Electron Microscopy (TEM/STEM) 9:45 AM June 15 114 MRI Bldg
Scanning electron microscopy (SEM) 9:45 AM June 22 541 Deike Bldg.
Analytical SEM 11:00 AM June 22 541 Deike Bldg.
X-ray Diffraction (XRD) 9:45 AM June 29 250 MRL Bldg.
Dielectric Characterization (25 min lecture only) 9:45 AM July 6 250 MRL bldg.
High temperature sintering lab (20 min lecture only) 10:15 AM July 6 250 MRL Bldg.
Focused Ion Beam (FIB) 9:45 AM July 13 114 MRI Bldg
TEM sample preparation 11:00 AM July 13 114 MRI Bldg
Orientation imaging microscopy (OIM/EBSD) 9:45 AM July 20 250 MRL Bldg.
Chemical analysis (ICP, ICP-MS) 9:45 AM July 27 541 Deike Bldg.
Atomic Force Microscopy (AFM) 9:45 AM August 3 114 MRI Bldg
Small angle x-ray scattering (SAXS) 9:45 AM August 10 541 Deike Bldg.
Particle Characterization 9:45 AM August 17 250 MRL
X-ray photoelectron spectroscopy (XPS/ESCA) 9:45 AM August 24 114 MRI Bldg
Auger Electron Spectroscopy (AES) 11:00 AM August 24 114 MRI Bldg
NOTE LOCATIONS: The MRI Bldg is in the Innovation Park near the Penn Stater Hotel; MRL Bldg. is on Hastings Road.
More information: www.mri.psu.edu/mcl
3. Materials Characterization Lab
www.mri.psu.edu/mcl
Materials Characterization Lab Locations
Bldg Telephone
MRL 863-7844
MRI 865-0337 MRI Bldg:
Hosler 865-1981 XPS/ESCA, SIMS,
E&ES 863-4225
TEM, HR-TEM, FE-
Auger, AFM, XRD
MRL Bldg:
Hosler Bldg:
SEM, XRD, OIM, DTA,
SEM, ESEM, FE-
DSC, TGA, FTIR, Penn Stater
SEM, EPMA, ICP,
Hotel
Raman, AFM, Powder,
E&ES Bldg: ICP-MS,BET, SAXS
dielectric, prep, shop,
SEM
IC, UV-Vis
Route 322
Steidle Bldg:
Atherton Street
Nanoindenter
(322 Business)
I-99
Park Ave.
0
0 0
0 0 0 0
Ave. 0
0 0 0 0
Park 0
Beaver
0
0
Stadium
0
0
0
Centre
0
0
Porter Road
Community
Univ
Shortlidg
Hospital
0
0
Burrowes Road
ersi
ty D
e
Pollock Road
Road
rive
North
Hastin
Deike Bldg: gs Ro
ad
College Ave.
4. Materials Characterization Lab
www.mri.psu.edu/mcl
Outline of ICP-AES segment
― a discussion of ICP-AES principles
― various problems encountered in ICP-AES
― sample dissolutions
― data reduction
― some applications
― ICP-MS
― a brief lab tour after ICP-MS talk
6. Materials Characterization Lab
www.mri.psu.edu/mcl
ICP-AES – inductively coupled plasma atomic
emission spectrophotometry
Electrons of an atom absorb energy and jump to higher energy levels
When they return to normal states, they emit characteristic photons of
energy
By isolating these photon wavelengths, we can determine the types and
concentrations of the elements present.
Concepts, Instrumentation, and Techniques in Inductively Coupled Plasma Optical Emission
Spectrometry, Boss and Freeden, Perkin Elmer
7. Materials Characterization Lab
www.mri.psu.edu/mcl
Sample Introduction
• Solution is drawn up by means of
a peristaltic pump
• Solution is turned into a fine
aerosol by a nebulizer
• Aerosol is introduced into a
plasma which excites the atomic
species in the aerosol
12. Materials Characterization Lab
www.mri.psu.edu/mcl
Common Problems in ICP-AES
Sampling and Sample Preparation
Spectral Interference
Matrix Effects
Instrumental Drift
13. Materials Characterization Lab
www.mri.psu.edu/mcl
Sampling and Sample Preparation
Are the samples representative of what you are trying to measure?
What steps should MCL take to make your samples representative?
Will any elements volatilize during sample preparation?
How much contamination can the sample tolerate during preparation?
14. Materials Characterization Lab
www.mri.psu.edu/mcl
Spectral Interference
Some elemental lines
may interfere with
others.
Best solution is to find
another spectral line.
Samples should be
scanned for possible
problems
Concepts, Instrumentation, and Techniques in Inductively Coupled Plasma Optical Emission
Spectrometry, Boss and Freeden, Perkin Elmer
15. Materials Characterization Lab
www.mri.psu.edu/mcl
Matrix Effects
Differing viscosities can affect amount of sample uptake
Matrices can change nature of plasma
Certain matrices (HF) can attack torch
Matrices can contain interfering spectral components
16. Materials Characterization Lab
www.mri.psu.edu/mcl
Combined Effects
Concepts, Instrumentation, and Techniques in Inductively Coupled Plasma Optical Emission
Spectrometry, Boss and Freeden, Perkin Elmer
17. Materials Characterization Lab
www.mri.psu.edu/mcl
Instrumental Drift
Instrument reading can drift over a period of time due to
physical changes in the optical system, or the configuration
of the plasma.
Standards need to be run at the beginning and end of each
run in order to estimate and correct for this drift.
18. Materials Characterization Lab
www.mri.psu.edu/mcl
Compensation
Standards run with every sample run
Drift Correction taken with every sample run
Matrix of standards should be closely matched with that of the
samples
Preliminary scans are taken to see if any spectral overlaps occur
19. Materials Characterization Lab
www.mri.psu.edu/mcl
Basic Analytical
Scheme
Concepts, Instrumentation,
and Techniques in Inductively
Coupled Plasma Optical
Emission Spectrometry, Boss
and Freeden, Perkin Elmer
20. Materials Characterization Lab
www.mri.psu.edu/mcl
Sample Dissolution for Solid Samples
Salt Fusions – typically lithium metaborate and sodium peroxide
Acid Digestions – nitric, hydrochloric, perchloric and hydrofluoric
Microwave Digestion – basically acid digestion in controlled
temperature and pressure vessels.
Samples are typically dried, ashed if necessary, and ground to <74
microns prior to dissolution procedures
21. Materials Characterization Lab
www.mri.psu.edu/mcl
Salt Fusion
Sample is mixed with lithium metaborate in a 1:9 ratio
Mix is melted at 900C and dissolved in a nitric acid solution
Pros:
Attacks geologicals and most ceramics
Provides a high concentration salt environment which dampens
any intersample matrix differences.
Cons:
Easily volatilized elements cannot be determined
High metal contents may prove difficult
23. Materials Characterization Lab
www.mri.psu.edu/mcl
Acid Digestion
Sample is allowed to dissolve in an acid mix.
Sample is typically heated to speed dissolution.
Pros:
Most direct dissolution, minimizing possible introduction of
contaminants
Usually best for metals
Cons:
Ineffective against geologicals and ceramics, especially if Si is
to be determined
Can be time consuming
25. Materials Characterization Lab
www.mri.psu.edu/mcl
Microwave Digestion
Sample is allowed under controlled temperature and pressure
conditions in a pressure vessel.
Pros:
Effective for a wide range of materials, especially those containing
organics
Direct method of dissolution, minimizing introduction of
contaminants
Cons:
Time consuming method development
Labor intensive
27. Materials Characterization Lab
www.mri.psu.edu/mcl
Data Reduction
Concepts, Instrumentation, and Techniques in Inductively Coupled Plasma Optical Emission
Spectrometry, Boss and Freeden, Perkin Elmer
28. Materials Characterization Lab
www.mri.psu.edu/mcl
What do the data mean?
Precision and accuracy
•Precision is how well the instrument replicates data over
time
•Accuracy is how close to the true value the observed
results will be
•Precision is generally on the order of 2 to 5 relative
weight percent
•Precision will vary from sample type to sample type
depending on a number of factors
33. Materials Characterization Lab
www.mri.psu.edu/mcl
Strengths of ICP-AES
• Can detect most cations and some anions
• Detection Limits down to parts per trillion for some elements
• Rapid simultaneous determination of selected elements
• Selective determination of other elements in sequential mode
• Good linear range – up to hundreds of ppms for alkalis
• Suitable for routine analyses of multiple samples
• Effective screening tool for ICP-MS samples
34. Materials Characterization Lab
www.mri.psu.edu/mcl
Weaknesses of ICP-AES
• Not effective for low levels of alkalis (less than 1-5 ppm)
• subject to matrix problems
• suitable standards required on every run
• Only elemental data is provided - no direct structural
information
• Does not provide, in most cases, parts per billion or parts per
trillion data
35. Materials Characterization Lab
www.mri.psu.edu/mcl
MCL capabilities:
Leeman Laboratories PS3000UV for ICP-AES
Lithium Metaborate and Sodium Peroxide Fusion capabilities.
Acid Digestion Facilities
MARS Microwave Digestion Capabilities
36. Materials Characterization Lab
www.mri.psu.edu/mcl
How to get started
1) contact myself, or John Kittleson to discuss your needs
2a) attend regular training session OR
2b) have one of us perform analysis and data interpretation
3) provide budget and fund number to keep us from getting yelled at.
37. Materials Characterization Lab
www.mri.psu.edu/mcl
Acceptable sample forms:
Solutions, preferably aqueous based with minimal or no HF
Minimal solution volume is 3-4 ml or more depending on analyses
Solids, can usually be dissolved using various techniques
39. Materials Characterization Lab
www.mri.psu.edu/mcl
Elemental Analyses by
High Resolution ICP-MS
John Kittleson
317 Holser Building
865-3385
jlk38@psu.edu
July 27, 2005
40. Materials Characterization Lab
www.mri.psu.edu/mcl
Summer Characterization Open Houses
Technique Time Date Location
Thermal analysis (TGA, DTA, DSC) 9:45 AM June 8 250 MRL Bldg.
Transmission Electron Microscopy (TEM/STEM) 9:45 AM June 15 114 MRI Bldg
Scanning electron microscopy (SEM) 9:45 AM June 22 541 Deike Bldg.
Analytical SEM 11:00 AM June 22 541 Deike Bldg.
X-ray Diffraction (XRD) 9:45 AM June 29 250 MRL Bldg.
Dielectric Characterization (25 min lecture only) 9:45 AM July 6 250 MRL bldg.
High temperature sintering lab (20 min lecture only) 10:15 AM July 6 250 MRL Bldg.
Focused Ion Beam (FIB) 9:45 AM July 13 114 MRI Bldg
TEM sample preparation 11:00 AM July 13 114 MRI Bldg
Orientation imaging microscopy (OIM/EBSD) 9:45 AM July 20 250 MRL Bldg.
Chemical analysis (ICP, ICP-MS) 9:45 AM July 27 541 Deike Bldg.
Atomic Force Microscopy (AFM) 9:45 AM August 3 114 MRI Bldg
Small angle x-ray scattering (SAXS) 9:45 AM August 10 541 Deike Bldg.
Particle Characterization 9:45 AM August 17 250 MRL
X-ray photoelectron spectroscopy (XPS/ESCA) 9:45 AM August 24 114 MRI Bldg
Auger Electron Spectroscopy (AES) 11:00 AM August 24 114 MRI Bldg
NOTE LOCATIONS: The MRI Bldg is in the Innovation Park near the Penn Stater Hotel; MRL Bldg. is on Hastings Road.
More information: www.mri.psu.edu/mcl
41. Materials Characterization Lab
www.mri.psu.edu/mcl
Materials Characterization Lab Locations
Bldg Telephone
MRL 863-7844
MRI 865-0337 MRI Bldg:
Hosler 865-1981 XPS/ESCA, SIMS,
E&ES 863-4225
TEM, HR-TEM, FE-
Auger, AFM, XRD
MRL Bldg:
Hosler Bldg:
SEM, XRD, OIM, DTA,
SEM, ESEM, FE-
DSC, TGA, FTIR, Penn Stater
SEM, EPMA, ICP,
Hotel
Raman, AFM, Powder,
E&ES Bldg: ICP-MS,BET, SAXS
dielectric, prep, shop,
SEM
IC, UV-Vis
Route 322
Steidle Bldg:
Atherton Street
Nanoindenter
(322 Business)
I-99
Park Ave.
0
0 0
0 0 0 0
Ave. 0
0 0 0 0
Park 0
Beaver
0
0
Stadium
0
0
0
Centre
0
0
Porter Road
Community
Univ
Shortlidg
Hospital
0
0
Burrowes Road
ersi
ty D
e
Pollock Road
Road
rive
North
Hastin
Deike Bldg: gs Ro
ad
College Ave.
55. Materials Characterization Lab
www.mri.psu.edu/mcl
Spectral Interferences
As75 @ 74.92160
Ar40Cl35 @ 74.93123
Element using high resolution
56. Materials Characterization Lab
www.mri.psu.edu/mcl
Spectral Interferences
Other methods:
-Mathematical interference corrections,
based on isotopic ratios, e.g. Rb87 corrected
for Sr87 using Sr88 and natural isotopic
abundances.
-Matrix removal, eg hydride generation (for
As, Se, Ge) and chromatographic separations.
-Collision/Reaction cells (on quadrupole
instruments)
57. Materials Characterization Lab
www.mri.psu.edu/mcl
Matrix effects
― Viscosity effects sample uptake rate. Use internal
standard.
― Matrix can effect rate of ionization in plasma. Use good
internal standard
― Matrix can contain interfering spectral components.
Remove matrix.
― Calibration standards must be matrix matched, or
calibration performed by standard addition.
58. Materials Characterization Lab
www.mri.psu.edu/mcl
Strengths of High Resolution ICP-MS
• Relatively free from spectral interferences
• Detection Limits down to parts per quadrillion for some elements
• Good linear range (over 9 orders of magnitude)
• Rapid determination of many elements
• Solid sampling possible via laser ablation
Weaknesses of High Resolution ICP-MS
• Expensive, fragile detector (cannot handle concentrations >1ppm)
• Cannot handle high total dissolved solids
• Somewhat tedious mass calibrations
59. Materials Characterization Lab
www.mri.psu.edu/mcl
Some Applications
• Trace metals in biological media (after dilution)
• Trace metals in drinking water (direct aspiration)
• Wear metals in lubricating oil (via microwave wet ashing)
• Trace metals in soil samples (via microwave wet ashing)
• Trace elements in glass via laser ablation
• Trace metals in native copper fragments via laser ablation
64. Materials Characterization Lab
www.mri.psu.edu/mcl
Laser Ablation Highlights
• Simplified matrix (reduced spectral interferences)
• Minimal sample preparation
• Very fast (rinse out times ~ seconds) saves $
• Good calibration standards hard to find
• Elemental fractionation
• Qualitative analysis (no standards) is easy
65. Materials Characterization Lab
www.mri.psu.edu/mcl
How to get started
1) Contact me to discuss your needs
2) Bring me your samples
3) Provide budget and fund number!
66. Materials Characterization Lab
www.mri.psu.edu/mcl
Acceptable sample forms:
Aqueous Solutions, dilute HCl, HNO3, HF
Minimal solution volume depends on concentration
Solids and slurries, minimum 100mg, depending on digestion method
Some solids may be suitable for laser ablation
Rock sections
Metal fragments
Pressed pellets
Anything that can be glued to a petrographic slide!
67. Materials Characterization Lab
www.mri.psu.edu/mcl
ICP-MS Fees
Instrument time (includes operator) = $90/hr
Staff time (sample prep, data workup, digestions, etc) = $30/hr
Consultation time to discuss your samples, data, etc is free.
Typical ‘Easy’ analysis – low resolution multielement determination of
dilute nitric acid solutions as received ~$15/sample)
Typical ‘Difficult’ analysis – medium or high resolution scans on complex
matrices, or refractory samples requiring digestion ~$50/sample
Method development and instrument setup are the most time
consuming. Cost per sample goes down with larger sample sets.
