Nature Nanotechnology, Published online: 12 June 2026; doi:10.1038/s41565-026-02182-5Aqueous cation transport in boron nitride nanotubes (BNNTs) is found to be generally enhanced under both concentration gradients and electric fields. BNNTs also transport Li ions fourfold faster than K ions. BNNT membranes may enable ‘blue’ osmotic energy and efficient ion separation.
