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!