Nuclear fusion fuel without toxic mercury

Nuclear fusion reactors , if and when they become practical , will need a steady supply of fuel. The source of that fuel is the uncommon lithium isotope lithium-6. And the established process to obtain Li-6 was banned in the US in 1963 because of the harmful mercury waste it generates. Now researchers have invented a simple electrochemical route to selectively grab Li-6 from aqueous solutions of lithium salt ( Chem 2025, DOI: 10.1016/j .chempr.2025.102486). The new mercury- free method works as well as the one based on the poisonous metal and could clear the path for industrial-scale production of fusion fuel, its developers say. Lithium exists in natural sources mainly as the isotope Li-7. Just 7.5% occurs as Li-6, which is critical for nuclear fusion. Bombarding Li-6 with neutrons generates the hydrogen isotope tritium, the most common fuel for fusion . Powering nuclear fusion reactors of the future will