Cation Exchange Synthesis and Unusual Resistive Switching Behaviors of Ag₂Se Nanobelts

Ag₂Se nanobelts are prepared through employing ZnSe nanobelts as templates via a facile cation exchange approach. The templates are derived from precursor ZnSe·0.5N₂H₄ nanobelts, which are synthesized by a simple hydrothermal method. As‐synthesized precursor nanobelts are with 200 nm in width and several hundreds of micrometers in length. Annealed in N₂, they are transformed into ZnSe nanobelts with preserving their initial morphology. Following with a complete replacement of Zn²⁺ by Ag⁺, Ag₂Se nanobelts with single crystalline are obtained via a cation‐exchange reaction. Combined with the Langmuir–Blodgett assembly technique, regular films of ZnSe nanobelts can be achieved on transparent glass substrates and Si wafers with interdigital Au electrode arrays. Further, the optical and electrical evolutions are investigated from ZnSe nanobelts to Ag₂Se nanobelts. Finally, the resistive switching characteristic are carefully explored for Ag₂Se nanobelts regularly arranged on interdigital Au microelectrodes. The results indicate that it is analogous to complementary resistive switching behaviors, which is different from that of traditional two terminal devices about previously reported Ag₂Se. In order to clarify this phenomenon, a possible mechanism has been proposed and indirectly demonstrated through in situ SEM (scanning electron microscropy) observation.