Enhanced electrical conductivity of copper by nitrogen-doped graphene

The demand for Cu with ultra-high conductivity has been growing across various industries. However, conventional approaches to enhance electrical conductivities, such as improving purity levels and reducing grain boundaries, have shown limited effectiveness. In this study, we synthesized a vapor-deposited nitrogen-doped graphene/Cu foil that exhibited a remarkable 14% improvement in electrical conductivity compared to the annealed Cu counterpart. The conductivity showed an initial increase and then a decrease with increasing nitrogen concentration, reaching a peak value at 2.7 at% nitrogen. Through Kelvin Probe Force Microscope and Density Function Theory calculations, we found that dual doping of copper-electrons and nitrogen significantly increased the carrier concentration, leading to enhanced surface charge potential differences. We believe that further improvement in conductivity can be achieved by carefully adjusting the doping level to balance carrier concentration and mobility.