Solution-phase synthesized iron telluride nanostructures with controllable thermally triggered p-type to n-type transition.

The switchability of electrical properties has recently attracted much attention due to its potential applications in memory, sensors, and resistive switches. Here, a solution-phase synthesis of iron telluride nanostructures with reversible and reproducible switching behavior between p- and n-type conduction is demonstrated by a simple change of temperature without crystal structure changes. The transition temperature of FeTe2 to switch from p-type to n-type is strongly dependent on the original ratio of the precursors and sintering time. Further studies confirm that the switching is derived from the valence change effect and a proof-of-concept thermally triggered p-n diode has been demonstrated.