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Protons and the Floating Water Bridge11th International Conference on the Physics, Chemistry and Biology of Water
Elmar C. Fuchs
Sir William George Armstrong, 1st Baron Armstrong * November 26, 1810 † December 27, 1900
Armstrong, William George, "Electrical Phenomena", in: THE ELECTRICAL ENGINEER, Feb 10 (1893) p154-155
Electrohydrodynamic liquid bridge
Bridge Formation
Visualisation:Photron SA1 High
Speed Camera (B/W). Slow Motion
Factor 120.
slow motion
Infrared Emissionwater emission 47°Cwater bridge emission
water emission 37°C
CO2 absorptionH2O vapor absorption
0
2400 2200 2000 1800 1600 1400 1200 1000 800
norm
. em
issi
on [
arb.
uni
ts]
wavenumber [cm]-1
5µm3µm = 3333 cm -1
12µm8µm
0
2400 2200 2000 1800 1600 1400 1200 1000 800
norm
. em
issi
on [
arb.
uni
ts]
wavenumber [cm]-1
Infrared Emissionwater emission 47°Cwater bridge emission
water emission 37°C
CO2 absorptionH2O vapor absorption
thermographic camera 1
thermographic camera 2
thermographic camera 1 thermographic camera 2
Infrared Emission
3-5µm region is as bright as 47°C, 8-12µm region as bright as 37°C waterThere is an additional, non-thermic emission at shorter wavelengthsThis emission is interpreted as result from a protonic band transition
E.C. Fuchs, A. Cherukupally, A.H. Paulitsch-Fuchs, L.L.F. Agostinho, A.D. Wexler, J. Woisetschläger and F.T. Freund, Investigation of the Mid-Infrared Emission of a Floating Water Bridge, J. Phys. D: Appl. Phys. 45 (2012) 475401
Measurement of the OH-vibration in an HDO moleculeDuration of vibration gives information about the H-bond network
Vibration stops faster in solid phase and last longer in liquid phase
hexagonal ice
liquid water
Ultrafast vibrational energy relaxation
300
400
500
600
700
OH
- st
retc
h vi
brat
iona
l life
time
/ fs
water bridge~ 25°C
ice
liquid water
ice 0°C
liquid water0°C
phase transition
Proton mobility
S( )water bridgewater in Al cylinder
inte
nsity
/ 10
a.u
.4
/ 10 µeV3
-10 -8 -6 -4 -2 0
3.0
2.5
2.0
1.5
1.0
0.5
0
"Quasi-elastic neutron scattering" - QENS
QENS data evaluation
/ 10 µeV3
800
-5 -4 -3 -2 -1 0
400inte
nsi
ty /
a.u
.
0
Q = 0.655871Å-1
Instrument resolution ( function, V)
S(Q, )
Lorentzian
Data pointFit: Lorentzian + function (V)
(Q)=DQ²
1+DQ²0
HWHM of the LorentzianRandom jump diffusion model:
Diffusion coefficient
/ µE
. . . .Q² / Å-
Water i Al li derWater ridge
Water °C si ulatio ith utliple s atteri g orre tio
Water ridge fit
Corre ted ater ridge ur e% o fide e i ter al
Water i Al li der fit
°C si ulatio% o fide e i ter al
Dwb= (26±10)·10-5 cm s-1Dw,50°C= 4.0 ·10-5 cm s-1
0,wb=(0.55±0.08) ps0,w,50°C= 1.00 ps
Proton mobility
Method to al ulate proto o ility µH / -7 m² V- s-
Stokes – Ei stei Diffusio oeffi ie t fro this easure e t
Te perature depe de t o E-field .
Ostrou o , Stuetzer a d Féli i .Féli i i pro ed ethod .
.
Charge mobility for EHD purposes has been reported "anomalously high"Stokes - Einstein relation allows to calculate proton mobility in the bridge
E. C. Fuchs, B. Bitschnau, A. D. Wexler, J. Woisetschläger, F. Freund, “A Quasi-Elastic Neutron Scattering Study of the Dynamics of Electrically Constrained Water,” J. Phys. Chem. 2015, 119 (52), pp 15892–15900
D=µqkBT
q
Proton jumps< l a > = D
l (water, 50°C) ~ 1.6 Å nearest neighbor interaction (Grotthuss)
l (wb, 50°C) ~ 3.0 Å next to nearest neighbor interaction
Quasi - free protonsQuantum mechanical interpretation of the Grotthus mechanism"Proton channel": proton conduction band across 3 water molecules"Band structure" is normally associated with a solid materialPhase is deteremined by the intermolecular bond strengths (H-bond)
Proton production, conduction and reduction
liquid flow gas flow ion flow
M. Sammer, A.D. Wexler, P. Kuntke, H. Wiltsche, N. Stanulewicz, E. Lankmayr, J. Woisetschläger, E.C. Fuchs, J. Phys. D: Appl. Phys 48 (2015) 415501
EIS of waterE peri e tal data
Fitted data
C
Raq
. E+
. E+
. E+
. E+
. E+
. E+
. E+-I
) /
. E+ . E+ . E+ . E+ . E+ . E+ . E+Re ) /
100 Hz - 107 Hz
E.C. Fuchs, M. Sammer, A.D. Wexler, P. Kuntke, J. Woisetschläger, J. Phys. D: Appl. Phys. 49 (2016) 125502
EIS of anolyte and catholyte
R1A
R2A
C1A
C2A
R1C
R2C
C1C
L
E peri e tal data a ol teFitted data a ol teE peri e tal data athol teFitted data athol te
. E+. E+ . E+ . E+ . E+ . E+ . E+ . E+
. E+
. E+
. E+
. E+
. E+
. E+
-I)
/
Re ) /
E.C. Fuchs, M. Sammer, A.D. Wexler, P. Kuntke, J. Woisetschläger, J. Phys. D: Appl. Phys. 49 (2016) 125502
Anolyte
A ol te, easure e t
A ol te, easure e t
A ol te, easure e t
-I)
/
-I)
/
-I)
/
Re ) / Re ) / Re )
H+ + e- 1/2 H2
Reduction destroys charge carriers, the impedance increases with each measurement
Catholyte
Cathol te, easure e t
Cathol te, easure e t
Cathol te, easure e t
-I)
/
Re ) /
2OH- 1/2 O2 + H2O +2e-
OH- are not present at pH 5.5, so the oxidation "frees" previously occupied protons, thus the impedance decreases with each measurement
Summary
An aqueous electrohydrodynamic floating bridge (a.k.a. "floating water bridge" -FWB) resembles a protonic resistorThe protonic charge flow heats up the water bridge and can be visualizedProtons are generated by electrolysis in the anolyte and are neutralized in the catholyteThe water in an FWB is in an electrically excited state with increased H-bond strength that lies inside the "no man's land" of the phase transition between ice and liquidIn this excited state protons reveal an increased mobility and travel through "proton channels"If the a FWB is stopped abruptly, excess protonic and aterprotonic charge remain in the water (~5mC/L)
Thank you for your attention.
Protons and the Floating Water BridgeElmar C. Fuchs1
With cordial gratitude to those who made this research possible and contributed to it: J. Woisetschläger2, A.D. Wexler1, H. Bakker10, F. Freund3, B. Bitschnau4, J. Teixeira5, A. Soper7, E. Del Giudice8, G. Vitiello9, B. Beuneu5, K. Gatterer4, H. Eisenkölbl4, G. Holler6, J. Tuinstra1, C. Buisman1, the companies in the AWP theme, and many more.
1. Wetsus, Centre of Excellence for Sustainable Water Technology, Agora 1, 8900 CC Leeuwarden, The Netherlands2. Graz University of Technology, Institute for Thermal Turbomachinery and Machine Dynamics, Austria3. NASA Ames Research Center, Moffett Field, Mountain View, CA, USA4. Graz University of Technology, Institute of Physical and Theoretical Chemistry, Austria 5. Laboratoire Léon Brillouin, Centre d'Études Nucléaires de Saclay, 91191 Gif-sur-Yvette Cedex, France6. Graz University of Technology, Institute of Electrical Measurement and Measurement Signal Processing, Austria7. ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon, OX11 0QX, United Kingdon8. Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano - 20133 Italy9. Dipartimento di Matematica e Informatica and INFN, Universitá di Salerno, Fisciano (SA) - 84084 Italy10. FOM Institute AMOLF, Amsterdam, The Netherlands
http://www.phdpositionswetsus.eu/
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