Uranium 235 over Polonium 210 in Nuclear Plants?

[Physics-GEEK]

I was researching on radioactive elements and found out that polonium is the most radioactive element and the most radioactive isotope of polonium (out of 33!) is polonium 210. So I was wondering why it isn't used in nuclear plants and bombs. I know that if a slow neutron was to hit uranium 235 or plutonium 239, it would cause a fission reaction and one of the main reasons for this is because uranium and plutonium are radioactive and have a high fission probability. But if polonium is more radioactive, shouldn't it produce more energy from a fission reaction and therefore cause much more damage (in the case of a nuclear bomb) and create much more energy (in the case of a nuclear power plant) than uranium-235 or plutonium 239? And if so, why don't they use polonium 210 in nuclear bombs and plants? And if not, why?
Thanks in advance!

 

[mfb]

found out that polonium is the most radioactive element

That statement does not make sense. Every element has isotopes with different lifetimes (some also have stable isotopes). Polonium-210 has a long lifetime compared to many other polonium isotopes.

Nuclear power plants use fission, the splitting of nuclei into two (sometimes three) smaller nuclei. They need isotopes that can undergo fission. Polonium-210 cannot. This has nothing to do with radioactivity.
There is also no large-scale source of Polonium-210.

 

[Physics-GEEK]

Ok thanks so much. I never knew that Polonium 210 wasn't a fissile isotope so thanks for clarifying.

 

[Bigjoemonger]

Any atom of sufficient size and instability can be made to fission if hit with enough energy. But the goal of using fission to create power is to create a self sustaining reaction. This requires the isotope to be fissile, meaning the isotope already wants to fall apart, you basically just have to touch it to get it going. Something like Po-210, you would put a ton of energy into get it to fission but you wouldn't get much energy out of it.

Fissile materials are U-233, U-235 and Pu-239.