Post on 13-Jan-2016
description
Liquid surface studied by particle spectroscopy
Preparation of liquid surface
MIES = Metastables Induced Electron Spectroscopy
NICISS = Neutral Impact Collision Ion Scattering Spectroscopy
NICISS (=Neutral Impact Collision Ion Scattering Spectroscopy)
Principle:
concentration depth profile
Formamide Surface
Valence orbitals
He+, 4.5keVNICISS He+, 4.5keV-Eloss
Formamide Surface
Valence orbitals
He+, 4.5keVNICISS He+, 4.5keV-Eloss -E
TBPBr /FA (tetrabutylphosphonium bromide in formamide)
NICISS (=Neutral Impact Collision Ion Scattering Spectroscopy)
CNO
PBr
0
5000
10000
15000
2 3 4 5 6 7 8
TOF [µs]
inte
nsity
[co
unts
/h/n
A]
solvent
0.01 molal
0.03 molal0.05 molal
0.20 molal0.41 molal
1.50 molal
Solution of Tetrabutylphosphonium Bromide in Formamide
0
1000
2000
3000
4000
5000
6000
4.0 4.5 5.0 5.5 6.0 6.5 7.0TOF [µs]
inte
nsi
ty [
cou
nts
/nA
/h]
spectrum of formamide
back groundsputtered hydrogen
fit to the back ground
oxygen step
-5
0
5
10
15
20
25
30
-30 -20 -10 0 10 20 30 40
depth [Å]
conc
ent
ratio
n [1
0-3
mo
l/cm
3 ]
measurement
Gibbs dividing plane
NICISS (=Neutral Impact Collision Ion Scattering Spectroscopy)
NICISS (=Neutral Impact Collision Ion Scattering Spectroscopy)
0
500
1000
1500
2000
2500
3000
3 3.5 4 4.5 5 5.5TOF [µs]
inte
nsi
ty [
cou
nts
/h/n
A]
solution
pure solvent
back ground of the solution ( x )
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
-30 -20 -10 0 10 20 30 40 50 60 70depth [Å]
con
cen
trat
ion
[10
-3m
ol/c
m3] Reihe1
Reihe2
Bu4P+
Br-
POPC in HPN
POPC (=1-Palmitoyl-2-Oleoyl-SN-Glycero-3-Phosphocholine)
HPN (=3-hydroxipropionitrile)
POPC in HPN
30
34
38
42
46
1.E-05 1.E-04 1.E-03 1.E-02
cPOPC [mol·kg-1]
[
mN
·m-1
]
0.0E+00
5.0E-11
1.0E-10
1.5E-10
2.0E-10
2.5E-10
1.0E-06 1.0E-05 1.0E-04 1.0E-03
cPOPC [mol·kg-1]
Ge
PO
PC [
mo
l/cm
2]
from surface tension
from NICISSsolute
excsolute dd G
solute
solute
soluteexcsolute
fdcd
adTR
d
lnln
ln
G
POPC in HPN
Activity coefficient of POPC below CMC
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
0.00E+00 2.00E-05 4.00E-05 6.00E-05 8.00E-05 1.00E-04 1.20E-04 1.40E-04 1.60E-04
cPOPC [mol/kg]
solutesoluteexcsolute
fdcdTR
dlnln
G
POPC in HPN
Evaluation of the chemical potential of POPC for all concentrations
POPC / HPNchem. Potential normalized to zero at lowest POPC-concentration
y = 2239.2Ln(x) + 26210
R2 = 0.9747
0.E+00
1.E+03
2.E+03
3.E+03
4.E+03
5.E+03
6.E+03
7.E+03
8.E+03
9.E+03
1.E+04
0.E+00 2.E-04 4.E-04 6.E-04 8.E-04 1.E-03 1.E-03 1.E-03 2.E-03 2.E-03 2.E-03
nominal concentration [mol/kg]
chem
pot
entia
l [Jo
ule/
mol
]
excsolute
solute
dd
G
POPC in HPN. Evaluation of the chemical potential of POPC.
Logarithmic plot demonstrates ideal behavior in pre-micellar range
POPC / HPNchem. Potential normalized to zero at lowest POPC-concentration
y = 2239.2Ln(x) + 26210
R2 = 0.9747
0.E+00
1.E+03
2.E+03
3.E+03
4.E+03
5.E+03
6.E+03
7.E+03
8.E+03
9.E+03
1.E+04
1.E-06 1.E-05 1.E-04 1.E-03 1.E-02
nominal concentration [mol/kg]
che
m p
ote
ntia
l [Jo
ule
/mo
l]
Pt clusters, embedded in IL
M rho [g/cm^3] n [mol]
Pt 195.1 19.77 6.15E-05
Polyvinylpyrrolidon 111.42 1.2 6.15E-04
BDiMIm 302.32 1.4 6.60E-04
CD3OD 36 0.847 1.65E-02
Sample from DC Knapp, Dr. Müller, Prof. Lercher, TU München
Polyvinylpyrrolidon Monomer Trimer
NO
H
HH
HH HH
H
H
NO
H
HH
HH HH
H
H
NO
H
HH
HH HH
H
HH H
NO
H
H
H
HH
HH HH
Pt clusters, embedded in IL
M rho [g/cm^3] n [mol]
Pt 195.1 19.77 6.15E-05
Polyvinylpyrrolidon 111.42 1.2 6.15E-04
BDiMIm 302.32 1.4 6.60E-04
CD3OD 36 0.847 1.65E-02
Sample from DC Knapp, Dr. Müller, Prof. Lercher, TU München
BDiMIm= Butyl Dimethyl Imidazolium Triflat
F
F
F
S-
O
OO
NN
C+
HH
H
H
HH
H H
HH
H H
H
Pt clusters, embedded in IL
13.9 m
solution from Dr. Müller
M rho [g/cm^3] n [mol]
Pt 195.1 19.77 6.15E-05
Polyvinylpyrrolidon 111.42 1.2 6.15E-04
BDiMIm 302.32 1.4 6.60E-04
CD3OD 36 0.847 1.65E-02
1.8 m
Preparation of thick layer:
spreading of 30 L on 4.8cm2
Preparation of thin layer:
dissolving in 8-fold amount of methanol &
spreading of 30L on 4.8cm2
Pt clusters, embedded in IL NICISS
Pt
Pt
S
S
F
F
O
O
N
N
C
C
-500
0
500
1000
1500
2000
2500
3000
2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
I korr1 (t)
selection for f it
H-recoil
steps
recoil & steps
13.9 m, 84°
Pt clusters, embedded in IL NICISS
1.8 m, 84°
Pt
Pt
S
S
F
F
O
O
N
N
C
C
-500
0
500
1000
1500
2000
2500
2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
I korr1 (t)
selection for f it
H-recoil
steps
recoil & steps
Pt
-50
0
50
100
150
200
250
300
2.5 2.6 2.7 2.8 2.9 3 3.1 3.2 3.3 3.4 3.5
TOF [s]
cou
nts
Pt 78°
Pt 68°
Pt 58°
Pt 48°
Pt 38°
Pt 28°
Pt 18°
Pt clusters, embedded in IL NICISS
1.8 m
Pt
Pt
S
S
F
F
O
O
N
N
C
C
-500
0
500
1000
1500
2000
2500
2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
I korr1 (t)
selection for f it
H-recoil
steps
recoil & steps
Pt
-100
0
100
200
300
400
500
600
2.5 2.6 2.7 2.8 2.9 3 3.1 3.2 3.3 3.4 3.5
TOF [s]
cou
nts
Pt 78°
Pt 68°
Pt 58°
Pt 48°
Pt 38°
Pt 28°
Pt 18°
Pt clusters, embedded in IL NICISS
Pt
Pt
S
S
F
F
O
O
N
N
C
C
-500
0
500
1000
1500
2000
2500
3000
2 2.5 3 3.5 4 4.5 5 5.5 6 6.5
I korr1 (t)
selection for f it
H-recoil
steps
recoil & steps
13.9 m
model consideration NICISS
surface
depth
surface
depth
model consideration NICISS
surface
depth
model consideration NICISS
surface
depth
model consideration NICISS
surface
depth
model consideration NICISS
surface
depth
model consideration NICISS
surface
depth
model consideration NICISS
surface
depth
model consideration NICISS
surface
depth
model consideration NICISS
surface
depth
model consideration NICISS
Pt
-100
0
100
200
300
400
500
600
2.5 2.6 2.7 2.8 2.9 3 3.1 3.2 3.3 3.4 3.5
TOF [s]
cou
nts
Pt 78°
Pt 68°
Pt 58°
Pt 48°
Pt 38°
Pt 28°
Pt 18°
Pt clusters, embedded in IL NICISS
13.9 m
Pt
-50
0
50
100
150
200
250
300
2.5 2.6 2.7 2.8 2.9 3 3.1 3.2 3.3 3.4 3.5
TOF [s]
cou
nts
Pt 78°
Pt 68°
Pt 58°
Pt 48°
Pt 38°
Pt 28°
Pt 18°
1.8 m
sample of Pt clusters, embedded in IL, goniographic NICISS
13.9 m 1.8 m
58°
-100
0
100
200
300
400
500
600
0 50 100 150 200
Fit
from exp.
78°
0
50
100
150
200
250
300
0 50 100 150 200 250 300
Reihe1
Reihe2
5%
70%
Pt concentration in bulkPt clusters
Pt atoms? percentage of this fraction is evaluated from 3D model
thin layer (~0.8nm) IL