N o t iz e n 1125
Potential Error Sources in Combined Electrochemistry/Neutron Detection Experiments
A. Rieker*, B. Speiser, K.-M . M angold, and M. H anack
Institut für Organische Chemie,
Universität Tübingen, A u f der M orgenstelle 18, D -7400 Tübingen 1, F R G
Z. Naturforsch. 46b, 112 5 - 1126 ( 19 9 1);
received January 25, 1991
Electrochemistry, Neutron Detection Experiments Recently, experimental evidence for the occur
rence o f electrochemically induced (“co ld ”) nu
clear fusion o f deuterium nuclei has been proposed by several groups [1 -3 ]. In particular, increased neutron counts and excess heat production o f the electrolytic cell have been reported. Although much debated, the results have neither been pro
ven nor refuted unequivocally [4],
We have electrolyzed a solution of 0.1 M LiOD in D 20 in a U-shaped cell (see. Fig. 1) between a Pt anode and a Pd cathode (Degussa; surface area
~ 2.7 cm2). The evolved gases were collected sepa
rately to avoid the reform ation of D 20 by surface catalysis on the noble metal electrodes. A constant current of 100 and 400 mA was lead through the cell by means o f an A M EL Model 552. The cath
ode part of the cell was placed between two scintil
lation counters arranged at a right angle. The out
put of the photom ultipliers was sorted by pulse
shape discrim ination analysis [5] into neutron and gam m a events and the impulses counted separate
ly. The electrolysis was conducted for 1000 s, while the events in the counters were followed. Then, the current was interrupted, the cell was moved away 5 m from the counters and the background was observed for 1000 s. This experimental cycle was repeated for 75 h.
The average numbers of neutron and gamm a counts in the electrolysis and background periods, respectively, were com pared. A small increase of the neutron events during electrolysis was found ( + 2.7% as referred to the background; the stand
ard deviation for all background neutron m easure
m ents was 2% ). However, at the same time the gam m a counts decreased. This result may be attri
buted to a shift in the photom ultiplier amplifica
tion causing the pulse shape discrimination elec
tronics falsely to indicate neutrons while gam ma events are occurring. A similar effect could be ob
served, when the electrolysis cell was replaced by a resistor and a constant current was passed through this dummy cell. The response of photom ultiplier devices to exterior magnetic and electrostatic fields is well known [6],
A lthough we did not attem pt to exactly control the heat production of the electrolysis cell, we ob
served a considerable tem perature increase o f the electrolyte during the experiment. At the same time the cell voltage U to m aintain a constant cur
rent increased, indicating a considerable increase o f cell resistance during the electrolysis. This effect
Fig. 1. Schematic set-up o f the electrochemistry/neutron de
tection experiment. A: ar
rangement o f electrochemical cell (1; top view) and neutron counters (2) with data collec
tion and interpretation elec
tronics (3) and galvanostat (4); B: side view o f the electro
chemical cell with a) Pd cath
ode and b) Pt anode.
* Reprint requests to Prof. Dr. A. Rieker.
V erlag der Z eitsch rift für N a tu r fo r sc h u n g , D -7 4 0 0 T ü b in gen 0 9 3 2 - 0776/91 /0 8 0 0 - 1 1 2 5 / $ 0 1 .0 0 /0
This work has been digitalized and published in 2013 by Verlag Zeitschrift für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative Commons Attribution-NoDerivs 3.0 Germany License.
On 01.01.2015 it is planned to change the License Conditions (the removal of the Creative Commons License condition “no derivative works”). This is to allow reuse in the area of future scientific usage.
Dieses Werk wurde im Jahr 2013 vom Verlag Zeitschrift für Naturforschung in Zusammenarbeit mit der Max-Planck-Gesellschaft zur Förderung der Wissenschaften e.V. digitalisiert und unter folgender Lizenz veröffentlicht:
Creative Commons Namensnennung-Keine Bearbeitung 3.0 Deutschland Lizenz.
Zum 01.01.2015 ist eine Anpassung der Lizenzbedingungen (Entfall der Creative Commons Lizenzbedingung „Keine Bearbeitung“) beabsichtigt, um eine Nachnutzung auch im Rahmen zukünftiger wissenschaftlicher Nutzungsformen zu ermöglichen.
1126 N o t iz e n
was avoided, when the anode com partm ent was purged with nitrogen during the background measurements. The evolved oxygen was blown out of the solution and the cell cooled to room tem per
ature in this part o f the experiment. A ttem pts to compare the heat production of a “cold fusion”
electrolysis cell to the Joule heat have been made under the assum ption th at the supply voltage to the cell was constant [1]. If U increases, the heat generated by passage of current through the resis
tive electrolyte increases as well.
A lthough these experiments do not conclusively prove or dismiss the hypothesis of electrochemical
ly induced nuclear fusion, we would like to point out that experiments and interpretations are prone to serious errors whose sources may not be ob
vious at first sight. We believe that the observa
tions reported here may offer an explanation for the irreproducibility observed in many laborato
ries all over the world attem pting to duplicate the original experimental work.
We greatfully acknow ledge the help o f G. J. Wagner, G . Mertens, and M. Koch (Physikalisches Institut der U niversität Tübingen) during the set-up, performance and analysis o f the experiments as well as the technical assistance o f G. Flätgen and L. Schubert.
[1] S. Pons, M. Fleischmann, and M. Hawkins, J. Elec- troanal. Chem. Interfac. Electrochem. 261, 301 (1989).
[2] S. E. Jones, E. P. Palmer, J. B. Czirr, D. L. Decker, G. L. Jensen, J. M. Thorne, S. F. Taylor, and J. Ra- felski. Nature 338, 737 (1989).
[3] M. Fleischmann, S. Pons, M. W. Anderson, L. J. Li, and M. Hawkins, J. Electroanal. Chem. Interfac.
Electrochem. 287, 293 (1990).
[4] B. Speiser and A. Rieker, N achr. Chem. Tech. Lab.
3 7 ,6 1 6 (1 9 8 9 ).
[5] H. U . Schmidt, M eßelektronik in der Kernphysik, p. 139ff., Teubner, Stuttgart (1986).
[6] R CA Photomultiplier M anual, RCA Electronic C om ponents, p. 34, Harrison, N.J. (1970).
