B' Kuppan

1
Ordered Mesoporous Carbon and its application in
DMF
National Centre for Catalysis Research Dept. of
Chemistry IIT Madras
B. Kuppan 06-02-09
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Introduction

• Porous solids - scientific and technological
  interest - ability to interact with atoms, ions
  and molecules at surfaces and throughout bulk of
  material
• Distribution of sizes, shapes and volumes of the
  void spaces in porous materials directly related
  to their ability to perform desired function in
  particular application.
• High SA/volume ratio provides a strong
  driving force to speed up thermodynamic processes
  that minimize free energy
• In high surface area materials the active
  sites are more isolated
• Materials with uniform pores - separate
  molecules on basis of size.
• Used as adsorbents, catalyst supports, and
  electrode materials.
• In recent years, DMFC have attracted
  significant attention because of their high
• energy transfer efficiency and low pollution
  causing potential.
• In this study Pt/OMCs anode catalyst for DMFC
  was prepared by a
• novel liquid reduction method using
  paraformaldehyde has reducing agent.

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Synthesis of MCM-41
6.56 g CTAB 0.69 g NaOH 57 ml H2O
1.5 ml TMAOH 15 ml H2O 4 g f.silica
Stirred 30 mints
Stirred 10 mints
Soln.X
Soln.Y
Soln.X Soln.Y Stirred 1.5 h
pH 11.2-11.5
Autoclave at 100 ºC for 1 day
Cal at 550 ºC
C.T. Kresge, M. E. Leonowicz, W. J. Roth, J. C.
Vartuli and J. S. Beck, Nature, 359 (1992) 710
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Synthesis of NCCR-1
1 g MCM-41 1.25 g sucrose 0.14 g H2SO4 5 g
H2O
Dried at 100 0C for 6 h and 160 0C for 6 h
Black powder
0.8 g sucrose 0.09 g H2SO4 5 g H2O
Dried at 100 0C for 6 h and 160 0C for 6 h
Carbonized at 900 0C for 6 h under N2 atm.
Washed with 10 HF at RT and with EtOH
NCCR-1
R. Ryoo, S. Hoon and S. Jun, J. Phys. Chem. B,
103 (1999) 7743
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XRD,TEM SAED
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N2 isotherm and pore size distribution MCM-41 and
NCCR-1
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Synthesis of MCM-48
J. S. Beck, J.C. Vartuli, W. J. Roth, M. E.
Leonowiez, C. T. kresge, K. D. Schmitt, C. Chu,
D. H. Oison, and E. W. Sheppard. S. B. McCullen,
J.L. Schlenker. J. Am. Chem. Soc., 114 (1992)
10834
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Synthesis of CMK-1
1 g MCM-48 1.25 g sucrose 0.14 g H2SO4 5 g
H2O
Dried at 100 0C for 6 h and 160 0C for 6 h
Black powder
0.8 g sucrose 0.09 g H2SO4 5 g H2O
Dried at 100 0C for 6 h and 160 0C for 6 h
Carbonized at 900 0C for 6 h under N2 atm.
Washed with 5 HF at RT and with EtOH
CMK-1
R. Ryoo, S. Hoon and S. Jun, J. Phys. Chem. B,
103 (1999) 7743
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XRD
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N2 isotherm and pore size distribution of MCM-48
and CMK-1
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Synthesis of SBA-15
4g P123 80 ml H2O 80 ml HCl (2M)
Stirred at 40 0C
8.8 g TEOS
Stirred at 40 0C for 24 h
Aged at 100 0C for 48 h
Washed EtOH and dried Cal at 550 0C
SBA-15
D.Zhao, J. Feng, Q. Huo, N. Melosh, G. H.
Fredrickson B. F. Chmelka and G. D. Stucky,
Science, 279 (1998) 548
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Synthesis of CMK-3
1 g SBA-15 1.25 g sucrose 0.14 g H2SO4 5 g
H2O
Dried at 100 0C for 6 h and 160 0C for 6 h
Black powder
0.8 g sucrose 0.09 g H2SO4 5 g H2O
Dried at 100 0C for 6 h and 160 0C for 6 h
Carbonized at 900 0C for 6 h under N2 atm.
Washed with 5 HF at RT and with EtOH
CMK-3
S. Jun, S. H. Joo, R. Ryoo, M. Kruk, M. Jaronice,
Z. Liu, T. Ohsuna and O. Terasaki, J. Am. Chem.
Soc, 122 (2000) 10712
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XRD TEM
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N2 isotherm and pore size distribution SBA-15 and
CMK-3
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Textural properties
Sample SBET (m2/g) pore vol.
(cc/g) pore size (nm)
MCM-41 1339 1.26
2.5 NCCR-1
1079 0.826
1.1 SBA-15 764
1.019 5.7 CMK-3 882
0.786 3.5 MCM-48
1544 0.83
2.4 CMK-1
773 0.57
3.7
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Preparation of 20,10 wt Pt/NCCR-1 , Pt/CMK-1 and
Pt/CMK-3
60 mg NCCR-1/CMK-1/ CMK-3 20 ml H2O 0.049 M
H2PtCl6 (2.1 ml)
Ultrasonication 30 min
Heated at 343 K / N2 for 3h
10 ml Na2CO3 Paraformaldehyde
Stirred 2.5 h
Filt. Washed dried under vaccum at 358 K for 20
h
Pt/NCCR-1, Pt/CMK-1 and Pt/CMK-3
W. Wei, C. Jieming, C. Yu and L. Tianhong, Chin.
J. Catal, 28 (2007) 17
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XRD pattern
10 wt Pt/MC
20 wt Pt/MC
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TEM SAED
20Pt/NCCR-1
20 Pt/CMK-3
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Electrocatalytic activity of the catalysts for
methanol oxidation
20 mg Pt/x 0.5 ml H2O 5 µl Nafion (5 )
Sonication 30 min
10 µl slurry on GC electrode
Dried at 308 K
1 M H2SO4 1 M MeOH
X NCCR-1, CMK-1 and CMK-3
25 mV/s at 298 K
V. Raghuveer and A. Manthiram J. Electrochem.
Soc, 152 (2005) A 1504
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Cyclic voltammograms
CVs of (a) Pt/NCCR-1, (b) Pt/CMK-1 and (c)
Pt/CMK-3 catalyst recorded in 1 M H2SO4 and 1 M
CH3OH with a scan rate of 25 mV/s at 298 K
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Chronoamperometric response recorded in 1 M
H2SO4 and 1 M CH3OH at potential 0.7 V
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Cyclic voltammograms 20 Pt/OMCs
CVs of (a) Pt/NCCR-1, (b) Pt/CMK-1 and (c)
Pt/CMK-3 catalyst recorded in 1 M H2SO4 and 1 M
CH3OH with a scan rate of 25 mV/s at 298 K
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Chronoamperometric response(20wt Pt/OMCs)
recorded in 1 M H2SO4 and 1 M CH3OH at potential
0.7 V
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7.90
8.10
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SEM, EDX of MCM-41 and NCCR-1
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TG-DTA of MCM-41 NCCR-1
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SEM and EDX
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TG-DTA of MCM-48 CMK-1
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SEM and EDX
CMK-3
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TG-DTA of SBA-15 CMK-3
SBA-15
CMK-3
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