Rhodium would literally be the ideal activation material were it not for costs. This was the activation material of choice for Enrico Fermi in his ground-breaking neutron activation work of the 1930’s which led to his Nobel prize.
Rhodium is made up of 100% Rh103; its only naturally occurring isotope. Rh103 has a thermal cross section of 145 barns for the Rh104 reaction. Rh103 max activates in a fixed thermal neutron field in about 5 minutes to Rh104 which has a 43-second half-life. Rh104 emits a powerful Beta particle with a maximum energy of 2.4 mev.
I include this reaction only as a side note in case some lucky fellow has or can get Rhodium foil. Rhodium used to be about $30.00/ounce in the 1930’s. As late as 1995, it was $500/ounce. In March, 2008 is was $10,000/ounce. You need not even guess what a 2”x 2” piece of custom rolled foil will cost you.
The price plunged in 2016-17 to about $600/ounce. Currently 2019 it is back up just a bit to $5000/ounce. Oh, why did I not buy back in 2017!!?
I attach the cross sectional ENDF plot.
Richard Hull
FAQ - Activation Materials - Rhodium
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Richard Hull
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FAQ - Activation Materials - Rhodium
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Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Jon Rosenstiel
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Re: FAQ - Activation Materials - Rhodium
As luck would have it, my Spectrace 6000 XRF analyzer sports a rhodium foil x-ray beam filter. Area of the filter is ~150 square-millimeters... should be large enough to see some results.
43-second Rh-104 emits several gammas, the strongest at 556 keV, but its intensity is only 2%, so detection will be difficult. A more likely candidate for the gamma spectroscopist would be 4.3-minute Rh-104m. It’s a prodigious gamma emitter, the strongest occurring at 51 keV with an intensity of 48%.
Jon Rosenstiel
43-second Rh-104 emits several gammas, the strongest at 556 keV, but its intensity is only 2%, so detection will be difficult. A more likely candidate for the gamma spectroscopist would be 4.3-minute Rh-104m. It’s a prodigious gamma emitter, the strongest occurring at 51 keV with an intensity of 48%.
Jon Rosenstiel
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Richard Hull
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Re: FAQ - Activation Materials - Rhodium
Let us know your results should you try it, Jon.
I, pitiably, had a fellow at my 98 Teslathon show up with two ounces of rhodium. He offered both to me for a total of $1,000.00 cash. I really wanted them, but baulked, figuring the price might drop a bit more. WRONGO Richard! The stuff never looked back and soared to and hung at 5,000 dollars until recently when it really went nuts. The price has plunged and is holding fairly steady today at about $9,100.00 per troy ounce. Such a deal!
Note, Rhodium is rarely traded as the ingoted metal in the market place! The normal one ounce comes chemically dissolved as a plating fluid sealed carefully in a thick poly bottle with a statement of one atomic troy ounce of rhodium contained.
Again, Good luck.
Richard Hull
I, pitiably, had a fellow at my 98 Teslathon show up with two ounces of rhodium. He offered both to me for a total of $1,000.00 cash. I really wanted them, but baulked, figuring the price might drop a bit more. WRONGO Richard! The stuff never looked back and soared to and hung at 5,000 dollars until recently when it really went nuts. The price has plunged and is holding fairly steady today at about $9,100.00 per troy ounce. Such a deal!
Note, Rhodium is rarely traded as the ingoted metal in the market place! The normal one ounce comes chemically dissolved as a plating fluid sealed carefully in a thick poly bottle with a statement of one atomic troy ounce of rhodium contained.
Again, Good luck.
Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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Carl Willis
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Re: FAQ - Activation Materials - Rhodium
Rhodium is used in self-powered detectors for some Babcock and Wilcox PWR power reactors (such as those at the Three Mile Island units). Neutrons activate the rhodium, decay beta particles carry some current to a collector electrode, and the minute current is sensed and produces a local power indication in the control room.
Attached pic shows an unused (obviously!) Reuter-Stokes RSN 202 self-powered rhodium detector. It contains a scant 125 mg of the metal. Look at the sensitivity to reactor neutrons: 6E-21 amp / n / cm^2 / sec.! The lowest current one might be able to measure reliably by an electrometer is in the range of 1E-15 A. No way to use a fusor to get a current reading, but I may activate the sensor end some day and look for rhodium gammas.
-Carl
Attached pic shows an unused (obviously!) Reuter-Stokes RSN 202 self-powered rhodium detector. It contains a scant 125 mg of the metal. Look at the sensitivity to reactor neutrons: 6E-21 amp / n / cm^2 / sec.! The lowest current one might be able to measure reliably by an electrometer is in the range of 1E-15 A. No way to use a fusor to get a current reading, but I may activate the sensor end some day and look for rhodium gammas.
-Carl
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Steven Sesselmann
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Re: FAQ - Activation Materials - Rhodium
Richard,
As some of you know, I am in the jewelry trade (my day job) and almost every jeweler has a rhodium plating solution (all white gold and some silver jewelry is Rhodium plated).
One could take a small piece of polished brass or copper to any jeweler and ask them to put a heavy coating of Rhodium on it.
Rhodium is expensive, but the amount of Rhodium that would plate on a 1" disk would be minimal, my guess about $1.00 worth, so don't let some jeweler charge you $100's
My one dollars worth..
Steven
As some of you know, I am in the jewelry trade (my day job) and almost every jeweler has a rhodium plating solution (all white gold and some silver jewelry is Rhodium plated).
One could take a small piece of polished brass or copper to any jeweler and ask them to put a heavy coating of Rhodium on it.
Rhodium is expensive, but the amount of Rhodium that would plate on a 1" disk would be minimal, my guess about $1.00 worth, so don't let some jeweler charge you $100's
My one dollars worth..
Steven
http://www.gammaspectacular.com - Gamma Spectrometry Systems
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
https://www.researchgate.net/profile/Steven_Sesselmann - Various papers and patents on RG
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John Futter
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Re: FAQ - Activation Materials - Rhodium
What a Fizzer
My wife and I enjoyed a personal guided tour in the NT Australia taking in Kakadu, Alice springs, Ularu on the proceeds of 28 grams of Rhoduim that I sold last July. Then it was US$ 3900 per troy ounce.
I should have waited I could have had the outing twice
Not all is lost I still have some but it is melted into some Tantalum foil that was wrapped around the outside but the whole bundle got too hot and now its a bit of a mess ( about half an ounce worth of Rhodium).
Might try activating it next time we are making some wear coupons out of iron
My wife and I enjoyed a personal guided tour in the NT Australia taking in Kakadu, Alice springs, Ularu on the proceeds of 28 grams of Rhoduim that I sold last July. Then it was US$ 3900 per troy ounce.
I should have waited I could have had the outing twice
Not all is lost I still have some but it is melted into some Tantalum foil that was wrapped around the outside but the whole bundle got too hot and now its a bit of a mess ( about half an ounce worth of Rhodium).
Might try activating it next time we are making some wear coupons out of iron