High structural stability in air of exfoliated multilayer graphene co-intercalated with cesium and ethylene

Abstract

Cs and ethylene were co-intercalated to form Cs-ethylene-graphite intercalation compounds (GIC) using multi-layer graphene (MLG) flakes prepared from the cleavage of highly oriented pyrolytic graphite (HOPG). The air stability of the resultant structure was examined by Raman scattering, for possible future applications such as large-scale integrated circuit (LSI) interconnects and transparent conductive electrodes. Compared with Cs- or FeCl3-intercalated MLG, the Cs-ethylene-MLG has remarkably higher structural air stability, and its initial stage 2 structure was maintained after four weeks of air exposure. In contrast, major de-intercalation of FeCl3 occurred in FeCl3-MLG. In Cs-MLG, some de-intercalation also occurred, but the stage 5 structure was maintained. The Cs-ethylene-MLG and Cs-MLG with good air stability in their structure are expected to have an n-type conduction system.