I have proposed here the "back side cell" concept, wherein a low
electrolysis potential or high pressure gas is used for front side
loading of an electrode, and a high potential is used for back side
de-loading and fusion generation. The high potential side of the
hydrogen loaded electrode, simply called the back side, requires an
appropriately constructed diffusion barrier to obtain the desired
effects. It is ideal if the de-loading hydrogen tunnels through the
barrier into a backside medium be it liquid or gas, to achieve the de-
loading. The back side medium is electrically isolated from the
front side medium except for connection via the loaded electrode.
Variations of the de-loading concept have been proposed including use
of positive back side potentials, negative back side potentials,
possibly with superimposed AC or pulsed waveforms. One variation
proposed included using a high temperature ceramic proton conductor
in lieu of a metallic electrode.
One goal is the prevention of fusion on the front side of the
tunneling barrier, where unfortunately it tends to occur. Hydrogen
fugacity and low energy catalyzed nuclear reactions (LENR) are
maximized at the front side of an internally located diffusion
barrier, even when no potential is used to drive the fusion, i.e.
merely pressure drives the diffusion. If energy releasing LENR occurs
on the internal front side of a diffusion barrier, disruption of the
barrier results. One means of dealing with this problem is
construction of, or at least maintenance of, the diffusion barrier
through an anodization. This might be achieved in some cases by
maintaining at least a small net current through the back side which
makes it on balance an anode. However, my experience in operating
purely AC electrospark cells, even in glow mode wherein two AC
electrodes were anodized such that electrospark was avoided, has been
that anodized barriers can also be built and maintained by use of
high voltage AC, and this has the added advantage that gas evolvement
is highly suppressed through recombination. If the barrier is
punctured and a gas bubble fills the defect, an arc can result
through the defect which makes it bigger and drains current away from
the rest of the electrode, reducing its effectiveness. Another
barrier problem is the possible accumulation of helium, which in some
materials will not diffuse, and thus the barrier is ultimately
rendered useless.
The ideal device would provide hydrogen nucleus tunneling to a high
electron density medium which would not be destroyed by LENR or
helium buildup. A principle difficulty with achieving this goal is
the fact that, for a given barrier size and field, electrons tunnel
with vastly higher probabilities, and thus flux. Since both the
electron and nucleus experience the same field across a barrier, the
only way address this problem appears to be to selectively increase
the tunneling barrier height for the electrons, or reduce it for the
nuclei.
Ceramic proton conductors may accomplish this to some degree. Protons
or deuterons are actually conducted in wave-like manner in conduction
bands in the medium - which is an electron insulator. Nuclei get a
free ride all the way to the surface. Therefor the barrier width is
essentially eliminated for the protons. Ceramic proton conductors
operate at high temperatures, thus helium diffusion may not be a
problem, at least for some. The back side medium would have to be
gas, preferably highly polar, so steam immediately comes to mind.
LENR may in fact erode the back side surface, but the proton
conductor can be very thick and thus take a log time before
replacement is necessary.
An alternative approach may be to derive an anodized film which is
also a proton conductor, or which at least presents differing barrier
sizes to electron vs nuclei tunneling. In fact, anodizing may produce
such an insulating but proton conducting barrier. Sodium
metasilicate layers do not seem to prevent hydrogen adsorbtion or
desorbtion, but some back side cell experimenting is needed to prove
that out. It is also possible that nanopores which characterize
anodized aluminum layers, and likely zirconium ad other metal
anodized layers, selectively permit nuclei exiting and retard
electron tunneling inward.
See Figs 4 and 5 of the article "Polycrystalline nanopore arrays with
hexagonal ordering on
aluminum", A. P. Li,a) F. Muller, A. Birner, K. Nielsch, and U.
Gosele. This is at:
http://www.mpi-halle.mpg.de/~porous_m/Publications/jvsta1999.pdf
Also see:
http://optonano.engin.brown.edu/publications/pdf/JAP02544.pdf
http://www.esco.co.kr/pdf/download/JPK/app0403-2.pdf
These provide some specific anodization methods for pore development.
Horace Heffner
http://www.mtaonline.net/~hheffner/
