Boron
Proton-boron fusion

B is also a candidate as a fuel for aneutronic fusion. When struck by a proton with energy of about 500 k eV, it produces three alpha particles and 8.7 MeV of energy. Most other fusion reactions involving hydrogen and helium produce penetrating neutron radiation, which weakens reactor structures and induces long-term radioactivity, thereby endangering operating personnel. The alpha particles from B fusion can be turned directly into electric power, and all radiation stops as soon as the reactor is turned off.
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