A hydrogen sensor was fabricated by utilizing a bundle of metal oxide nanostructures whose growth positions were selectively controlled by utilizing graphene, which is a carbon of atomic-unit thickness. To verify the reducing ability of graphene, it was confirmed that the multi-composition metal oxide V2O5 was converted into VO2 on the graphene surface. Because of the role of graphene as a reducing catalyst, it was confirmed that ZnO and MoO3 nanostructures were grown at high density only on the graphene surface. The fabricated gas sensor showed excellent sensitivity.
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF), funded by the Ministry of Science, ICT & Future Planning (NRF-2019R1A2C1006972).