Hydroxide-based magneto-ionics: electric-field control of a reversible paramagnetic-to-ferromagnetic switch in α-Co(OH)₂ films

Here we demonstrate highly effective hydroxide-based magneto-ionics in electrodeposited α-Co(OH)2 films. The α-Co(OH)2, which is a room temperature paramagnet, is reversibly switched between paramagnetic-ferromagnetic states after electrolyte gating.