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Scientists Turn Nuclear Waste Into Diamond Batteries (newatlas.com)
Scientists at the University of Bristol have found a way to convert thousands of tons of nuclear waste into man-made diamond batteries that can generate a small electric current for thousands of years. New Atlas reports: How to dispose of nuclear waste is one of the great technical challenges of the 21st century. The trouble is, it usually turns out not to be so much a question of disposal as long-term storage. Disposal, therefore is more often a matter of keeping waste safe, but being able to get at it later when needed. One unexpected example of this is the Bristol team's work on a major source of nuclear waste from Britain's aging Magnox reactors, which are now being decommissioned after over half a century of service. These first generation reactors used graphite blocks as moderators to slow down neutrons to keep the nuclear fission process running, but decades of exposure have left the UK with 104,720 tons of graphite blocks that are now classed as nuclear waste because the radiation in the reactors changes some of the inert carbon in the blocks into radioactive carbon-14. Carbon-14 is a low-yield beta particle emitter that can't penetrate even a few centimeters of air, but it's still too dangerous to allow into the environment. Instead of burying it, the Bristol team's solution is to remove most of the c-14 from the graphite blocks and turn it into electricity-generating diamonds. The nuclear diamond battery is based on the fact that when a man-made diamond is exposed to radiation, it produces a small electric current. According to the researchers, this makes it possible to build a battery that has no moving parts, gives off no emissions, and is maintenance-free. The Bristol researchers found that the carbon-14 wasn't uniformly distributed in the Magnox blocks, but is concentrated in the side closest to the uranium fuel rods. To produce the batteries, the blocks are heated to drive out the carbon-14 from the radioactive end, leaving the blocks much less radioactive than before. c-14 gas is then collected and using low pressures and high temperatures is turned into man-made diamonds. Once formed, the beta particles emitted by the c-14 interact with the diamond's crystal lattice, throwing off electrons and generating electricity. The diamonds themselves are radioactive, so they are given a second non-radioactive diamond coating to act as a radiation shield.
CVD is a low pressure ionized gas crystallization process. It produces gemstone class diamonds.
The researchers would likely benefit more from using the Russian hydraulic form compression method of producing said diamonds, because it is much cheaper. It does not produce single, large crystal diamonds without defects the way CVD does, but we aren't trying to make jewelry here. We are interested in trapping the emitted beta particles (high energy electrons emitted from the nucleus) in the lattice and using the high bandgap semi conductive properties of the diamond to transport those electrons as a reliable source of current.
Without exact figures for how many tons of irradiated graphite there is, how energy intense CVD us compared to compressive forming, and how efficient the two end products are, I cannot even begin to answer your question though.
Even if there is a big deficit, it might still be worthwhile, due to the immense savings on sequestration costs, and maintenance costs of these batteries.
You don't eat bananas, either, do you? Because those monstrosities not only turn out beta radiation, they produce nearly-impossible-to-shield gamma radiation, and they occasionally even spit particles of pure antimatter. Boo!
Carrying around a tiny radioactive battery in every phone, watch, pacemaker, and remote control seems like a great idea,
Fine, power your bitcoin asic in the closet.
Or move the remote control a few centimeters away from you when not actively clicking.
From the summary: "Carbon-14 is a low-yield beta particle emitter that can't penetrate even a few centimeters of air"
The first hydraulic presses (tetrahedral presses) were made by an american engineer Tracy Hall. The "diamond makers" is a great book that discusses these early efforts and the long history of trying to create artificial diamond. Also not sure about efficiency, but high pressure formed artificial diamonds tend to be way more defective - a problem if you're trying to create semiconductor properties of a beta voltaic. CVD actually produces diamonds with less flaws than nature.
Yes it is electricity BUT it's measured in picoamps.
That was the turning point of my life--I went from negative zero to positive zero.
I wonder how it's output/mass compares to that of a radioactive thermal generator.
TFA claims it can do 0.2 mW/g (vs 8 for alkaline battery). It looks like Pu-238 decay heat is around 540 mW/g, with half life of 90 years, but 90-95% of that will be lost in conversion to electricity, and it will require substantial mass for that conversion and shielding.