1 WATSURF 2013

Summary

1. Why investigate confined water as a Cu II ligand?

2. Preliminaries – Porous materials and water as a Cu II

ligand

3. Cu II loading in hydrophillic pores

4. Cu II loading in hydrophobic pores by pressure

5. Comparison of the two types of nano pores

4. Concluding remarks

2 WATSURF 2013

WATSURF 2013 3

Water purification – nitrate uptake

Catalysis in water - green chemistry

Biological interest - Copper modified porous silica (CuPS) surfaces for

antibody detection by ELISA techniques

Why investigate confined water as a Cu II ligand?

SBA-15 Cu

H2O

CuPS-P CuPS Polystyrene

WATSURF 2013 4

POLYMERIZATION AT THE INTERFACE

Template

Acid medium Basic medium

Si

OH2+

OSi Si

O O-

SiO

OSi SiO

Si

OCH2CH3

OCH2CH3

CH3CH2O

CH3CH2O

TEOS

MCM-41 SBA-15

OH

OH OH HO

OH

OH OH HO

OH

OH OH HO

OH

OH OH HO

OH

OH OH HO

OH

OH OH HO

OH

OH OH HO

OH

OH OH HO

OH

OH OH HO

OH

OH OH HO

Mesoporous Templated Silicate materials

WATSURF 2013 5

Cu longer bond lengths

Water as a Cu II ligand

Cu2+

O H

H [Cu(H20)6]2+

2+

Cu II aqua complexes - classed as labile according to Taube’s rules

- water exchange in the 106 to 108 s-1 range

Octahedral Cu II complexes are known to submit to the Jahn-Teller effect!

A stretched octahedral structure is expected where 2 out of the 6 bond lengths

are longer (weaker bond strengths).

WATSURF 2013 6

Schematic representation of [Cu(NH3)3(H2O)3]2+ and [Cu(NH3)4(H2O)2]

2+

approaching and bonding to the SBA-15 surface.

Cu II loading in hydrophilic pores

SBA-15 + Cu II (aq) NH4OH

7 WATSURF 2013 Brodie–Linder, N., Besse, R., Audonnet, F., LeCaer, S., Deschamps, J.,

Imperor-Clerc, M., Alba–Simionesco, C. Microporous Mesoporous Materials, 132,

(2010) 518.

- O

- O

CuLx

12% Cu II w/w

20% Cu II w/w

TEM images

WATSURF 2013 8

Characterization of SBA-15 Cu

400 500 600 700 800 9000,00

0,02

0,04

0,06

0,08

0,10

0,12

0,14

Arb

itra

ry u

nit

s

Wavelength (nm)

30% Cu

20% Cu

10% Cu

7% Cu

682

700

Diffuse reflectance spectra

1250 1000 750 5000,00

0,05

0,10

0,15

3600 3200

Arb

itra

ry u

nit

s

Wavenumber (cm-1

)

0%

12%

16%

20%

960 cm-1

533 cm-1

424 cm-1

1060 cm-1

IR spectra

Perkin-Elmer AAnalyst 100 Atomic Absorption Spectrophotometer

Treatment of SBA-15-Cu with 2% HNO3 to

solubilize Cu II atoms by breaking the Cu-O

surface bonds.

0 5 10 15 20 25 300

5

10

15

20

% l

os

s H

2O

% Cu in SBA-15

Loss of H2O as a function of %Cu II in SBA-15 Cu materials

Amount of adsorbed H2O increases as Cu II loading increases 9 WATSURF 2013

200 400 600 80080

82

84

86

88

90

92

94

96

98

100

% l

oss i

n w

eig

ht

T°C

SBA-15

SBA-15 Cu (7%)

TGA (Thermogravimetric Analysis)

H20 Si Si Si

H

Si

OH O O O H H

Cu(H20)x

O O

WATSURF 2013 10

HO OH OH

OH OH

HO

0,0 0,2 0,4 0,6 0,8 1,00

500

1000

1500

arb

itra

ry u

nit

s

p/po

native

12%

16%

20%

0,6 0,8 1,0 1,2 1,40,0

2,0x109

4,0x109

6,0x109

8,0x109

1,0x1010

1,2x1010

Inte

nsi

ty

2

12% SBA-15 Cu

SBA-15

d100

a

N2 volumetric adsorption SAX (Small Angle X-ray diffraction)

Substrate (solid)

adsorbate

Structural properties

WATSURF 2013 11

Linear

acclerator

Ar

Chromato

electron pulses of 10 ns

Si

O

H

Si

O

H

Si

O

H

Si

O

H

10 MeV electrons

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

10 MeV electrons

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

Si

O

H

H

.O.

.H

H

O

H

H2

SBA-15 surface

Sample holder Gas Chromatograph

H2 formation by electron irradiation of SBA-15 Cu materials

WATSURF 2013 12

0 10 20 30 40

0,0

1,0x10-9

2,0x10-9

3,0x10-9

4,0x10-9

5,0x10-9

H2

(m

ol)

pe

r g

ram

LW

C S

BA

-15

% Cu in SBA-15

SBA-15 Cu (20 %)

Copper inhibits H2 formation (water bonded to copper atoms)

Brodie-Linder N., Le Caër S., Alam M. S.,Renault J.P.,

Alba-Simionesco C., PCCP, 12 (42), (2010), 14188.

Si Si Si

H

Si

OH O O O H H

O O

Cu(H2O)x

Aqueous Cu II in a Hydrophillic vs a Hydrophobic Nanopore

Cu(H2O)x

O O Cu(H2O)x

Bonded to the surface Free from the surface

Hydrophillic Nanopore Hydrophobic Nanopore

13 WATSURF 2013

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Pressure line

Pressure cell

Pressure

Compressor mesoporous

materials

- OSi(CH3)3

- OSi(CH3)3

CuLx MCM-41 OSi(CH3)3/SBA-15 OSi(CH3)3+ Cu II (aq) Under pressure*

4000 bar

*Deschamps J., Audonnet F., Brodie-Linder N., Schoeffel M.,

Alba-Simionesco PCCP, 12, (2010) ,1440.

Preparation of MCM-41 OSi(CH3)3-Cu and SBA-15 OSi(CH3)3-Cu materials

MCM-41/ SBA-15 + SiCl(CH3)3 CHCl3

NEt3

MCM-41 OSi(CH3)3/SBA-15 OSi(CH3)3

Without pressure

With pressure

MCM-41- OSi(CH3)3

15 WATSURF 2013

MCM-41- OSi(CH3)3 –Cu II

4000 bar

Cu II solution

WATSURF 2013 16

SBA-15-OSi(CH3)3

4000 bar

SBA-15-OSi(CH3)3-CuII

Cu II solution

Characterization of MCM-41 C16 materials

1600 1400 1200 1000 800 600 4000,0

0,2

0,4

0,6

0,8

4000 3800 3600 3400 3200 30000,0

0,2

0,4

0,6

4000 3800 3600 3400 3200 30000,0

0,2

0,4

0,6

Arb

itra

ry u

nit

s

Wavenumber (cm-1

)

-O-Cu-O

-OSi(CH3)

3-Cu

-OSi(CH3)

3

IR spectra

17 WATSURF 2013

0,0 0,2 0,4 0,6 0,8 1,00

2

4

6

8

10

12

14

% C

uII

Concentration (mol L-1)

pressure

standard

Copper II Loading as a function of Cu II solution

N2 adsorption isotherms

0 20 40 60 80 1000

200

400

600

Vcm

3/c

m3

p/po

- OH

-OSi(CH3)3

-OCuO-

-OSi(CH3)3Cu

N2 volumetric adsorption

0,0 0,2 0,4 0,6 0,8 1,00

200

400

600

800

-OH

-OCuO

V/V

p/po

0,0 0,2 0,4 0,6 0,8 1,00

200

400

600

800

OSi(CH3)3

OSi(CH3)3Cu

V/V

p/po

Hydrophobic surface Hydrophillic surface

Effect of Copper II loading in the pores

N2 adsorption isotherms

18 WATSURF 2013

MCM-41-OSi(CH3)3Cu

MCM-41-OSi(CH3)3

MCM-41-OH

19 WATSURF 2013

Concluding remarks

Copper II loading on the surface of mesoporous silicate materials always

results in a rise in the amount of confined water.

Water can be confined in hydrophobic pores using Cu II and our

pressure method.

Confined Water as a Cu II ligand plays an important role in determining

the hydrophillic/hydrophobic nature of MTS materials.

The number of water molecules bonded to the confined Cu II atoms

can be modified by dehydration creating a reversible process.

Perspectives: closer look at water in the CuII hydrophobic pores

20

WATSURF 2013

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Collaborators

Christiane Alba-Simionesco, LLB Saclay

Claudia Pantelei, LLB Saclay

Fabrice Audonnet, University Pascal Blaise, Clermond Ferrand

Johnny Deschamps, ENSTA, Paristech

Marcus Schoeffel, Polytechnique, Paristech

Sophie LeCaer, Laboratoire de Radiolyse, Saclay

Jean-Phillip Renault , Laboratoire de Radiolyse, Saclay

Regis Besse, University of Cergy Pontoise

Nadege Lubin-Germain, SOSCO, University of Cergy Pontoise

Florian Gallier, SOSCO, University of Cergy Pontoise

Elisa Peroni, SOSCO, University of Cergy Pontoise

Patricia Beaunier, Service de microscopie électronique,

Université Pierre et Marie Curie