Copper has long been a standard material in electrical conductors, but advanced applications require a lower weight and higher electrical conductivity.
Copper-graphene (Cu-Gr) composites have been proposed as a potential solution, with the hypothesis that graphene could improve the conductivity of copper.
This promise is challenged by a new study supported by NASA and led by Dr. Yuanyue Liu from the TMI and the Walker Department of Mechanical Engineering. The research, titled "Effects of Graphene Doping in the Electrical Conductivity of Copper," has been published in Advanced Functional Materials.
Using state-of-the-art first-principles calculations of electron transport, the researchers discovered that the inclusion of graphene in copper does not necessarily result in increased electrical conductivity. Contrary to the belief that graphene would enhance conductivity, the study shows that the composite's conductivity is lower than that of pure copper. This is attributed to increased electron scattering within the composite.
In addition to these findings, the research highlights that compressive strain along the (111) plane of copper significantly enhances its conductivity. This effect was confirmed experimentally, providing a new understanding of how mechanical strain can be used to optimize the performance of copper-based conductors. In contrast, tensile strain was found to have little effect on conductivity.
The study offers important new insights into the behavior of copper-graphene composites and advances the understanding of how strain can influence electrical conductivity. These findings have implications for the development of next-generation electrical conductors and other advanced materials.
The first authors of this paper are Dr. Chenmu Zhang and Dr. Zhongcan Xiao, both from TMI. The corresponding authors also include Prof. Michael Cullinan at UT Austin and Prof. Mehran Tehrani at UCSD.
For more details on the study, you can access the full article here.
