Reconfigurable van der Waals Ferroionic Barristor for Multifunctional Nanoelectronics.

2D materials have been interested in recent years due to their unique properties and enormous potential in various fields. In particular, 2D ferroionics with both ferroelectricity and ionic conductivity shed light on new possibilities for van der Waals nanoelectronics. Here, supported by theoretical calculations and electrical characterizations, the reconfigurable van der Waals ferroionic barristor that can be used in multifunctional electronics including resistive devices and steep‐slope transistors is reported. Large modulation on the device properties is achieved by electrically driven migration and redistribution of mobile ions. The memory device shows an unprecedented long‐term stability with a switching ratio of ≈1010. Utilizing this ferroionic nature, 2D transistors able to beat the Boltzmann tyranny, with different gate configurations, are designed. The subthreshold swing (SS) exhibits sub‐60 mV per decade values over five decades of the drain current with a minimum of 12.1 mV per decade. This work paves the way for investigating the symbiotic relationship of ferroelectricity and ionic activities in van der Waals ferroionics and highlights their applications in advanced nanoelectronics. [ABSTRACT FROM AUTHOR]