Adam G. Kelly: All-printed thin-film transistors from networks of liquid-exfoliated nanosheets

Adam G. Kelly Trinity College Dublin All-printed transistors consisting of interconnected networks of various types of two-dimensional nanosheets are an important goal in nanoscience. Using electrolytic gating, we demonstrate all-printed, vertically stacked transistors with graphene source, drain, and gate electrodes, a transition metal dichalcogenide channel, and a boron nitride (BN) separator, all formed from nanosheet networks. The BN network contains an ionic liquid within its porous interior that allows electrolytic gating in a solid-like structure. Nanosheet network channels display on:off ratios of up to 600, transconductances exceeding 5 millisiemens, and mobilities of >0.1 square centimeters per volt per second. These devices also show scaling of on-currents with network thickness and volumetric capacitance. The large double-layer capacitance, while hindering switching speeds, allows these devices to carry high currents at low drive voltages relative to other devices with similar mobility.  Kelly, Adam G., et al. "All-printed thin-film transistors from networks of liquid-exfoliated nanosheets." Science 356.6333 (2017): 69-73. Adam Kelly is a PhD student under Prof. Jonathan Coleman in the CRANN & AMBER research centre at Trinity College Dublin. He received his B.Sc. in Experimental Physics from Trinity College in 2014. His professional interests include liquid-phase processing of nanomaterials for use in printed electronics.