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.