Nanostructured Bimetallic, Trimetallic and CoreShell FuelCellCatalysts with Controlled Size, Composi

1
Nanostructured Bimetallic, Trimetallic and
Core-Shell Fuel-Cell Catalysts with Controlled
Size, Composition, and Morphology (NIRT
CBET-0709113) Jin Luo1, Peter N. Njoki1, Derrick
Mott1, Bridgid Wanjala1, Rameshwori Loukrakpam1,
Bin Fang1, Xiajing Shi1, Khalid Alzoubi2, Susan
Lu2, Lichang Wang4, Bahgat Sammakia3, and
Chuan-Jian Zhong1, Department of 1Chemistry,
2Systems Science and Industrial Engineering,
3Mechanical Engineering, State University of New
York at Binghamton 4Department of Chemistry
Biochemistry, Southern Illinois University at
Carbondale, USA
Abstract Active, robust, and low-cost catalyst
is a key component for the commercialization of
fuel cells. The development of effective
strategies for the synthesis and processing of
multimetallic nanoparticles with controllable
size and composition is an important approach to
the catalyst preparation. This poster focuses on
the results from an investigation of bimetallic,
trimetallic, and core-shell nanoparticle
catalysts for fuel cell testing. The
characterization of the size, shape, composition
and phase properties of the multimetallic
nanoparticles and catalysts is described. The
electrochemical characterization of the
electrocatalytic properties of the catalysts for
fuel cell reactions is discussed along with
preliminary evaluation of some of the catalysts
under fuel cell testing conditions. The results
are also discussed in terms of activity and
stability of the catalysts based on theoretical
computation and statistical optimization to gain
fundamental insights into the design and control
parameters of fuel cell catalysts.
Fuel Cell and Catalysts
Bimetallic Nanoparticles Catalysts
Core-Shell Catalysts
Trimetallic Nanoparticles Catalysts

• High conversion efficiency
• Low pollution
• Light weight
• High power density

HTEM-EDX analysis
XRD of AunPt100-n/C
Pt
Preparation of PtVFe Nanoparticles
Existing Catalysts
V

• Low activity
• High Pt loading (high cost)
• Poor stability

Fe
Bulk
Nanoscale
Goals
? bimetallic composition determined from XRD
? data for bulk bimetallic metal system

• Reduce Pt loading
• Increase activity stability
• Understand design parameters
• Discover new catalysts

EDX Analysis of Composition
? frozen states of bulk bimetallic metal system
? bimetallic composition determined from
DCP-AES.
Fuel cell voltage Ecell ENernst
?act (i.e., ?act(cathode) - ?act(anode))
?ohmic
Pt32 V14 Fe54 /C
FTIR of CO Adsorption on AunPt100-n/SiO2
Fuel Cell Testing
Optimization Analysis
Relative Mass Activities for ORR
DFT Calculations
General correlation between two different
properties (Activity and Stability) for catalyst
(M1)x(M2)yPt1-x-y
ORR Oxygen Reduction Reaction
Fuel cell polarization curves of MEA with Pt/C
catalyst (20 loading). Pt loading 1.0 mg/cm2,
MEA active area 5 cm2.
Pareto optimization
Activity

PtNiZr
Optimal balanced activity and stability for
(Ni)x(Zr)yPt1-x-y
??
Characterization of electrocatalytic activity and
stability of the multimetallic catalysts using
RDE technique
Preliminary results from density functional
theory (DFT) calculations for O2 on PtmVnFel and
Pt nanoparticles show that the oxygen reduction
reaction is favorable on PtmVnFel in comparison
with Pt due to direct or spontaneous O2
dissociations. O2 dissociation on PtmVnFel
nanoparticles is limited by the active sites
(Pt-V or Pt-Fe) available.

Optimization and Identification of the best
catalysts
Comparison of relative electrocatalytic
activities. Examples Pt32V14Fe54/C (31
loading),Pt31Ni34Fe35/C (30 metal loading) and
standard Pt/C (20 metal loading) catalysts.
Insert Rotating Disk Electrode data for
catalysts on glassy carbon electrode in 0.5 M
H2SO4. (5 mV/s, and 2000 rpm).
Stability
Evaluation of the activity and durability of
membrane electrode assembly (MEA) in fuel cells
Selecting M1 and M2 can be based on Pareto
optimization plot. A set of solutions is said to
be Pareto optimal if it cannot be improved upon
without hurting one of the objectives.
Support
Summary
References

• Bimetallic, trimetallic, and core-shell
  nanoparticle catalysts with controlled size,
  composition and phase properties have been shown
  to exhibit high electrocatalytic activity.
• Experimental, theoretical, and statistic
  analysis results have shown that the size and
  composition of multimetallic nanoparticles play
  an important role in regulating the
  electrocatalytic activity and stability.
• These multimetallic nanocatalysts are being
  characterized and evaluated under fuel cell
  conditions in terms of activity and durability.

• Luo, J. Wang, L. Mott, D. Njoki, P. N.
  Kariuki, N. N. Zhong, C. J. He, T., J. Mater.
  Chem., 2006, 16, 1665.
• Luo, J. Han, L. Kariuki, N. N. Wang, L. Mott,
  D. Zhong, C. J. He, T., Chem. Mater., 2005, 17,
  5282.
• D. Mott, J. Luo, P. Njoki, Y. Lin, L. Wang, C. J.
  Zhong, Catalysis Tod., 2007, 122, 378
• X. Shi, J. Luo, P. Njoki, Y. Lin, T. H. Lin, D.
  Mott, S. Lu, C. J. Zhong, Ind. Eng. Chem. Res.,
  2008, 47, 4675.
• Zhong, C. J. Luo, J. Njoki, P. N. Mott, D.
  Wanjala B. Loukrakpam, R. Lim, S. I-I. Wang,
  L. Fang, B. Xu, Z., Energy Environ. Sci,
  2008, 1, 454.
• J. Luo, L.Y. Wang, D. Mott, P. Njoki, Y. Lin, T.
  He, Z. Xu, B. Wanjala, S. I-Im Lim, C. J. Zhong,
  Adv. Mater., in press.

NIRT
For More Information
Email Contact C.J. Zhong cjzhong_at_binghamton.ed
u Web http//chemistry.binghamton.edu/ZHONG/zho
ng.htm