Resistive switching in Si₂Te₃ nanowires

As a silicon-based chalcogenide, semiconducting Si2Te3 has recently attracted attention as an emerging layered 2D material. Here, single-crystalline Si2Te3 nanowires (NWs) are synthesized by chemical vapor deposition (CVD). The Si2Te3 NWs grow along the [0001] direction, which is perpendicular to the 2D layers. The NWs exhibit a unique reversible resistance switching behavior driven by an applied electrical potential, which leads to switching of the NWs from a high-resistance state to a low-resistance state. This switched state is stable unless the opposite potential is applied to switch the resistance back. It is also noted that the polarity of the initially applied potential along the NWs defines the switch on and off directions, which become permanent once set. In combination with theoretical calculations, the resistance switching is explained by an internal structural change resulting from the applied potential. This novel resistance switching property for the silicon-based 2D materials is not only interesting for fundamental exploration but also holds promise for applications in memory devices.