Here is a link to an article in New Scientist about nanomaterials that can convert radioactivity directly into electricity:

http://www.newscientist.com/article/dn13545-nanomaterial-turns-radiation-directly-into-electricity.html

Would this process have an application in High Density Plasma (Focus) Fusion?

rashidas - 24 November 2010 09:48 PM

Here is a link to an article in New Scientist about nanomaterials that can convert radioactivity directly into electricity:

http://www.newscientist.com/article/dn13545-nanomaterial-turns-radiation-directly-into-electricity.html

Would this process have an application in High Density Plasma (Focus) Fusion?

What I gather from the article is that this is a fission-oriented approach which won’t be of much help to a Focus Fusion aneutronic fusion reactor… because the output of an FF is basically alpha particles, x-rays and heat.

The coils around the FF alpha beam already convert the energy of the alphas to electricity much more efficiently… and much more cheaply… than the gold-stuffed nanotubes would

... what this is, is Heinlein’s isotopic batteries, is what it is….

on the contrary,
“Radioactive particles that slam into the gold push out a shower of high-energy electrons. They pass through carbon nanotubes and pass into the lithium hydride from where they move into electrodes, allowing current to flow.”

this shower of high-energy electrons process is like what we want to see happen in the onion.

vansig - 27 November 2010 06:25 PM

on the contrary,
“Radioactive particles that slam into the gold push out a shower of high-energy electrons. They pass through carbon nanotubes and pass into the lithium hydride from where they move into electrodes, allowing current to flow.”

this shower of high-energy electrons process is like what we want to see happen in the onion.

Very interesting observation, V.; but there’s no indication, of course, that X-rays would initiate any such shower from the gold nano.  But tweaking materials or geometry might do the trick.

“Radioactive particles that slam into the gold push out a shower of high-energy electrons.”

Was it really so hard for newscientist to say if it was alpha, beta or gamma radiation?  I can’t figure out if what they made is trivial (capturing energy from alphas/betas) or worthwhile (gammas).  I’m guessing that it is gammas.

Unanswered questions:
What happens when high energy gammas don’t hit the gold particles but hit the carbon nanotubes?
Why Gold?

gold has lots of ground-state electrons to stand up and be pushed around. so xrays, gammas, and betas should all do that as they scatter through the medium.

seems sorta like a shottky junction, with plenty of eddy currents near the absorption site.
a device doing this well would run a lot cooler compared to a heat engine. but, what’s the ultimate efficiency, i wonder?