Counter-ion Dependent, Longitudinal\ud Unzipping of Multi-Walled Carbon\ud Nanotubes to Highly Conductive and\ud Transparent Graphene Nanoribbons

摘要

Here we report for the first time, a simple hydrothermal approach for the bulk production of highly\udconductive and transparent graphene nanoribbons (GNRs) using several counter ions from K2SO4, KNO3,\udKOH and H2SO4 in aqueous media, where, selective intercalation followed by exfoliation gives highly\udconducting GNRs with over 80% yield. In these experiments, sulfate and nitrate ions act as a co-intercalant\udalong with potassium ions resulting into exfoliation of multi-walled carbon nanotubes (MWCNTs) in an\udeffective manner. The striking similarity of experimental results in KOH and H2SO4 that demonstrates\udpartially damaged MWCNTs, implies that no individual K1, SO422 ion plays a key role in unwrapping of\udMWCNTs, rather this process is largely effective in the presence of both cations and anions working in a\udcooperative manner. The GNRs can be used for preparing conductive 16 kVsq21, transparent (82%) and\udflexible thin films using low cost fabrication method