Electrical conduction of palladium-decorated multi-layered graphene oxide effected by hydrogen dissociation

Multi-layered graphene oxide (MGO) and palladium-decorated MGO (PdGO) are electrically evaluated as a function of H2 pressure up to 20 bar to elucidate an interaction between molecular hydrogen and PdGO. As H2 pressure increases, the electrical conductance (G) of MGO also increases while that of PdGO decreases. Using atomic force microscopy, X-ray photoelectron spectroscopy, and Fourier transform-infrared spectroscopy analysis, we found that MGO reduction due to H2 accounts for the increase in G of the MGO. For PdGO, an increase of OH groups was observed, which shows that PdGO was oxidized when exposed to high H2 pressure. The PdGO oxidation can be explained by a hydrogen spillover effect and the decrease of G may be due to this behavior.