Dr. Victor Vega-Mayoral, 28.3.2019, 13:00, Seminar room F7

Fabrication of thin film transistors and energy storage devices from liquid phase exfoliated nanosheets

Dr. Victor Vega-Mayoral, CRANN & AMBER research centers, Trinity College Dublin, School of physics, Trinity College Dublin

Abstract:

Transition metal dichalcogenides has been one of the most promising family of materials for a lustrum. Strong light matter interaction and high mobilities when exfoliated down to the monolayer. Liquid phase exfoliation produces dispersions of few-layer TMDCs. Due to the liquid nature of the final sample it is possible to print or spray these dispersions to produce thin films of 2d flakes. We will talk about the fabrication of transistors and energy storage devices.

TiS2 is a promising material for energy storage devices. Its application has been reduced due to a fast degradation in open atmosphere. Our latest results proofs how degradation can be avoided by carefully choosing the solvent. We have fabricated stable batteries with high cyclability and capacities close to the theoretical value.

Mixed networks of conducting and non-conducting nanoparticles show promise in a range of applications where fast charge transport is important. While the dependence of network conductivity on the conductive mass fraction (Mf) is well understood, little is known about the Mf-dependence of mobility and carrier density. I  will show here a detailed characterization of thin film transistors as a function of the WS2-graphene Mf. Here, we use electrolytic gating to investigate the transport properties of spray-coated composite networks of graphene and WS2 nanosheets.

Poster [PDF]