Chemical Engineering Seminar Speaker: Susan Fullerton

Two-dimensional (2D) materials are molecularly thin, layered materials held together by van der Waals forces. Because charge moves freely in the 2D plane, these materials have potential application in electronics; however, conventional doping strategies have not been developed for 2D materials. An alternative approach is to use electrolyte gating. Under an applied gate voltage, ions in the electrolyte create an electrostatic double layer (EDL) at the interface between the electrolyte and the semiconductor; the EDL can induce sheet carrier densities on the order of 10¹⁴ cm^-2 for both electrons and holes – more than one order of magnitude larger than conventional gating techniques. Our group seeks to translate EDL gating from a measurement tool for exploring transport to an active device component that enables new functionality at the ultimate limit of scaling. I will describe our work using polymer electrolytes to dope transistors based on graphene and transition metal dichalcogenides (TMDs), and our development of new types of electrolytes for applications in security and information storage.  Specifically, I will introduce a monolayer electrolyte developed by our group and show the first device characteristics on graphene and MoS2 FETs.