Improving the capacity of graphene to transport electricity

Graphene is widely studied due to its mechanical and electrical properties, which makes it useful in applications ranging from solar cells to biomaterials and conductive materials. Single-layer graphene films have the highest purity but are expensive to fabricate, leading to the use of few-layer films or bulk graphene. Moyano et al. studied the effects of electron beam irradiation on the properties of a few-layer graphene film.

The researchers irradiated electrochemical exfoliated graphene with an electron beam of up to 10 keV. They evaluated the changes in sheet resistance using the Van der Pauw method and the chemical structure of graphene films with UV-VIS, Raman and XPS spectroscopy.

“We expected the radiation could damage the structure because of the deposited energy,” said author Esteban Irribarra. “However, it turned out that after the interaction of the electrons with graphene, the capacity of the structure to transport electricity was improved.”

They found that sheet resistance and defect density decreased as the energy of incident electrons increased. Specifically, the sheet resistance was reduced by 17.3% after the sample was irradiated with a 10 keV electron beam.

“The reduction of defect density on the irradiated samples caused by the removal of oxygen content on graphene flakes led to this result,” said Irribarra. “Consequently, electron beam irradiation based on defect engineering could be used to modify the electrical conductivity of graphene films.”

This result demonstrates the possibility of improving the performance of few-layer graphene. Using defect engineering, a balance between expensive high-purity single-layer graphene and cheaper few-layer graphene films with improved properties can be achieved depending on the application.

Source: “Chemical and electrical modifications of few-layer graphene films via sub-10 keV electron beam irradiation,” by Karla Moyano, Carlos Reinoso, Steven Núñez, Beatriz Pérez, Cristian Santacruz, César Costa, and Esteban Irribarra, Journal of Vacuum Science and Technology: B (2023). The article can be accessed at https://doi.org/10.1116/6.0002123 .

This paper is part of the “Papers from the 65th International Conference on Electron, Ion, And Photon Beam Technology and Nanofabrication (EIPBN 2022)” collection, learn more here .