Cyclic chlorine trap-doping for transparent, conductive, thermally stable and damage-free graphene

Abstract

We propose a novel doping method of graphene using the cyclic trap-doping method with low energy chlorine adsorption. Low energy chlorine adsorption for graphene chlorination avoided defect (D-band) formation during the doping by maintaining the π-bonding of the graphene, which affects conductivity. In addition, by trapping chlorine dopants between the graphene layers, the sheet resistance could be decreased by ∼ 88% under optimized conditions. Among the reported doping methods, including chemical, plasma, and photochemical methods, the proposed doping method is believed to be the most promising for producing graphene with extremely high transmittance, low sheet resistance, high thermal stability, and high flexibility for use in various flexible electronic devices. The results of Raman spectroscopy and sheet resistance showed that this method is also non-destructive and controllable. The sheet resistance of the doped tri-layer graphene was 70 Ω per sq. at transmittance of 94%, and which was maintained for more than 100 h in a vacuum at 230 °C. Moreover, the defect intensity of graphene was not increased during the cyclic trap-doping.

A Library of Doped-Graphene Images via Transmission Electron Microscopy

“…The dry doping of graphene by low energy plasmas is an interesting, new, damage-free method [19][20][21][22][23][24]. The method could be applied to other plasma systems such as neutral beams or ion beams.…”

“…Copyright 2011 American Chemical Society. (d-g) are reprinted with permission from [19]. Copyright 2014 Royal Society of Chemistry.…”

Recent Advances in Doping of Molybdenum Disulfide: Industrial Applications and Future Prospects

“…From a different perspective, plasma doping is emerging as a promising option for layer‐by‐layer stacking of heterostructural hybrid materials by controlling the plasma species, plasma doping concentration, plasma power, and treatment time. This is accomplished without damage from ion bombardment or the formation of defects or disorders on the MoS 2 structure using low energy radical doping and has been applied successfully for graphene doping with plasma, by using cyclic trapped plasma doping . Moreover, the plasma‐assisted doping technique is a very easy scale‐up and mass‐production technique.…”

X‐Ray Spectroscopic Investigation of Chlorinated Graphene: Surface Structure and Electronic Effects

“…Chlorination has also been demonstrated in other carbon‐based materials, such as carbon nanotubes, graphite, graphite oxide (GO), Janus graphene, and nanographenes, manifesting various electronic applications such as lithium‐ion batteries, transparent conducting films, and electrochemical devices. Several different chlorination methods have been successfully developed, including photochlorination, cyclic chlorine trapping, direct exfoliation, electrophilic substitution, and plasma‐based chlorination . High coverage (C 2.2 Cl) of adsorbed chlorine on single‐sided graphene was recently realized experimentally, which paved the road to realize double‐sided chlorinated graphene and could ultimately enable band gap engineering.…”