Institute for Micromanufacturing Louisiana Tech University Synchrotron Studies for Tackling Technical Challenges in the Hydrogen Economy { } { Research

Institute for MicromanufacturingLouisiana Tech University

Synchrotron Studies for Tackling Technical Synchrotron Studies for Tackling Technical Challenges in the Hydrogen EconomyChallenges in the Hydrogen Economy

{{Research into Novel Materials for Emerging Energy Applications}}

Tabbetha A. Dobbins1,2

1. Institute for Micromanufacturing, Louisiana Tech University, Ruston, LA2. Dept. of Physics, Grambling State University, Grambling, LA


November 5, 2009


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- The Fossil Fuel-based economy has limitations;- An alternative fuel cell energy infrastructure (PEM Fuel Cells

and Solid Oxide Fuel Cells) will penetrate energy markets;- Technical challenges facing the PEM fuel cell are

nevertheless substantial;- Creative solutions are needed to tackle our societal need for

“cleaner and greener” energy.

Animation courtesy of: http://www.humboldt.edu

?

H2 Fuel???

“A (n) Inconvenient Truth” (about Energy Production)


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Storage Weight % (System) 6 3.4

Energy Efficiency % 97 88

Energy Density (W-h/L) 1100 1300

Specific Energy (W-h/kg) 2000 1080

Cost ($/Kw-h) 5 18

Operating Temperature (oC) Up to 50oC Up to 50oC

Start-up Time (sec) 15 <15

Hydrogen Loss (scc/hr/L) 1.0 1.0

Cycle Life (#) 500 20-50

Refueling Time (min) <5 undetermined

Recoverable Usable Amt 90% >90%

Target Performance

Targets Table Reproduction from Millikan and Rossmeissl Aug. 14, 2002 Workshop

Image from Satyapal, Petrovic, Thomas (Scientific American, April 2007)


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DoE Targets for Hydrogen Storage Materials


Synchrotron (High Flux) X-rays Source at CAMD (LSU in Baton Rouge, LA)

• 1.3Mile, 7GeV ring of electrons in storage ring.• 38 experimental sectors • Small-Angle X-ray Scattering (SAXS), 3D Imaging • Collaborators: Jan Ilavsky and Francesco DeCarlo

Advanced Photon Source (APS)at Argonne National Laboratory

• 0.3 Mile, 1-2GeV ring of electrons in storage ring.• 15 experimental sectors• X-ray Absorption Spectroscopy, 3D Imaging, and SAXS• Collaborators: Amitava Roy

Synchrotron Accelerators


CAMD

SSRL

ALSAPS

CHESS NSLSSRC

SURF

Is the only SR source in the South!

Synchrotron Radiation Facilities in the US


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• Catalysis: What is role of transition catalysts in the hydrogen discharge and recharge reaction? How are non-reversible products formed and what are their roles in catalysis?

• Kinetics: What fundamental limits hydrogen desorption kinetics? What are mass transport limitations in hydrogen storage materials?

• Improved Research Tools: What instrumentation developments are needed for improved examination of atomic local structure (0.1 – 2nm) and microstructure (2nm – 1000 m)?

Some Grand Challenge Areas in H2 Storage Research


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Research Highlights Fundamental Materials Research Problems–

(1) Role of Catalyst still not well understood; (2) Slow diffusion and reaction rates should be addressed.

– 3D Imaging of Interphase Boundary Area between LiBH4/MgH2 and TiN/NaAlH4• Dobbins T.A., Decarlo F., Ziao, X., Ukpai W., Narase Gowda S. (To be published)

– Formation of TiAlx Alloys during introduction of TiCl3 catalyst to NaAlH4• Dobbins T.A., Abrecht M., Uprety Y., Moore K., ”An X-ray Photoemission Electron Microscopy Study of the

Formation of Ti-Al Phases in 4 mol % TiCl3 Catalyzed NaAlH4 During High Energy Ball Milling”, Nanotechnology, 20, 204014 (2009).

– Microwave irradiation for desorption of H2 from NaAlH4• Krishnan R., Agrawal D., Dobbins T.A.,“Microwave Irradiation Effects on Reversible Hydrogen Desorption in

Sodium Aluminum Hydrides (NaAlH4)”, Journal of Alloys and Compounds, 470 [1-2] 250 (2009).

– TiCl3 dopant mitigating Na+ and Al3+ diffusion rates in NaAlH4• Dobbins, T.A., Bruster E.B., Oteri, E.U., Ilavsky J., ”Ultrasmall-Angle X-ray Scattering (USAXS) Studies of

Morphological Trends in High Energy Milled NaAlH4 Powders”, Journal of Alloys and Compounds 446-447 pp 248-254 (2007).

– Thin polymer films containing Ti3+ overlayed onto NaAlH4• Kamineni V., Lvov Y.M., Dobbins T.A. “Layer-by-Layer Nanoassembly Using Formamide as a Working Solvent”,

Langmuir 23 pp 7423-27 (2007).


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• Tomography can guide this work by yielding interfacial contact area.• Tomography also Offers a means to define active crystallographic

surfaces (coupled with Wulff construction of images and by DFT).

3D Imaging (Computed X-ray Tomography)

50 mol % TiN in NaAlH4 (17 keV) (imaged at CAMD)

2 NaAlH4 + 2TiN 2TiAl + 2 NaN + 4 H2(g)

QuickTime™ and aYUV420 codec decompressor

are needed to see this picture.


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0 minute mill time (blended)

1 minute mill time

5 minute mill time

25 minute mill time

125 minute mill time

TiAl

TiAl3

EXAFS: TiAl and TiAl3 formation during introduction of TiCl3 catalyst to NaAlH4

TiAl3

Normalized Absorption Radial Distribution Function


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-0.20

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1550 1560 1570 1580 1590

Corrected Energy (eV)

No

rmal

ized

Ab

sorp

tio

n (

a.u

.)

Absorption (a.u.) - Al with Ti overlap Absorption (a.u.) - no Ti overlap

20

25

30

35

40

45

50

55

60

65

450 455 460 465 470 475 480

Energy (eV)

Ab

so

rpti

on

(a

.u.)

Absorption (a.u.) - Ti-rich region Absorption (a.u.) - No Ti region

NaAlH4+4 mol % TiCl3 after high energy milled for 25 minutes. XPEEM data were collected at the VLS PGM beamline at the Synchrotron Radiation Center (SRC), Madison, WI. (Collaborator: Michael Abrecht)

Ti

Al Na

Cl

5m 5m

5m5m

X-ray Photoemission Electron Microscopy (XPEEM): TiAlx formation during high energy milling

Al K-edge Spectra

Ti L-edge Spectra

25 Minute Mill


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0 min mill time 1 min mill time

25 min mill time

SEM images of undoped NaAlH4 powders blended for 2 minutes in dry N2 glovebox and milled for (a) 0 minutes; (b) 1 minute; (c) 5 minutes; and (d) 25 minutes.

(a) (b)

(c)

5 min mill time

(d)

Quantitative Parameter to describe microstructure (in terms of surface area)

Small-Angle X-ray Scattering (SAXS)

100

101

102

103

104

105

106

107

108

109

Inte

nsi

ty [

cm-1

]

0.001 0.01 0.1

q [A-1

]

S129_NaAlH4_undoped_0 S133_NaAlH4_undoped_1 S137_NaAlH4_undoped_5 S141_NaAlH4_undoped_25 S145_NaAlH4_undoped_125

Mon, Sep 04, 2006, 4:59:37 PM

SAXS Data

• p~-3 for High surface area. • p~-4 smoother colloidal particle (lowest surface area)• SA~rDs~rpr6

In Collaboration with Jan Ilavsky (Advanced Photon Source)

Dobbins, T.A., Bruster E.B., Oteri, E.U., Ilavsky J., JALCOM 446-447 p 248 (2007).


Summary and Future Plans:

• Dept. of Energy: Energy Frontier Research Centero The Center for Atomic-Level Catalyst Design. (Lead: James Spivey @ LSU)o Center involves 8 institutions in the U.S. (LaTech, GSU, GaTech, UFl, Penn State, Tulane

and abroad (Univ. of Utrecht).o The overall objective of LaTech/GSU work is to explore catalyst structure-property

relationships which dictate fuel conversion reaction mechanisms and reaction rates using synchrotron x-ray scattering and x-ray absorption spectroscopy.

• NSF Faculty Early Career Development Awardo The objective of this proposal is to understand the influence of catalytic additives in

enhancing atomic mobility and desorption rates in metal hydrides (specifically, NaAlH4 and LiBH4) by incorporating x-ray and neutron studies.

o Two new courses cross-listed at LaTech, LSU and GSU. (1) Synchrotron Studies and (2) Alternative Energy

o High school design challenge: Design H2 tank for Fuel Cell Vehicle.

QuickTime™ and aYUV420 codec decompressor

are needed to see this picture.

X-ray Data for unique Insight into structure of materials Synchrotron Courses for training new

generation of students in formal settingUndergraduate Student Mentoring

High School Fuel Cell Workshops

C C


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Graduate Students: Corisma Robinson (XANES); Vimal Kamineni

(EXAFS/XANES)Shathabish Narase

Godwa (Neutron Studies)

Collaborators:• CAMD (EXAFS/XANES): Amitava Roy and Greg Merchan • CAMD (Tomography): Kyunming Ham and Les Butler• SRC (XPEEM): Michael Abrecht• APS (USAXS): Jan Ilavsky• APS (Tomography): Francesco Decarlo and Xianghui Xiao• LaTech IfM: Daniela Mainardi, Phani Krisha Dathara, Yuri Lvov

Acknowledgments

Funding Sources:• Department of Energy, Office of Basic Energy Sciences (Contract No.: DE-FG02-05ER46246).• National Science Foundation, Division of Materials Research (Contract No.: DMR-0508560).• National Science Foundation, CAREER Award Program (Contract No.: DMR-0847464).• Louisiana State Board of Regents Support Fund, RCS Program• Louisiana State Board of Regents Support Fund, PFUND Program

Undergraduate Students: Youaraj Uprety (XPEEM Analysis); Kristan Moore (X-ray Diffraction); Whitney Fisher (Tomography);

www2.latech.edu/~tdobbins


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Thank You.

www2.latech.edu/~tdobbins

Documents

Institute for Micromanufacturing Louisiana Tech University Synchrotron Studies for Tackling Technical Challenges in the Hydrogen Economy { } { Research