Effect of substitutional impurities on the electronic transport properties of graphene

• Electronic transport in doped graphene ribbon is studied using DFT.
• B, N and Si atoms are used to substitute the center or edge carbon atoms.
• Si-doping results in better electronic transport.
• The transmission spectrum also depends on the location of the dopants.
• The are explained in terms of electron localization near the impurities.

Density-functional theory in combination with the nonequilibrium Green's function formalism is used to study the effect of substitutional doping on the electronic transport properties of hydrogen passivated zig-zag graphene nanoribbon devices. B, N and Si atoms are used to substitute carbon atoms located at the center or at the edge of the sample. We found that Si-doping results in better electronic transport as compared to the other substitutions. The transmission spectrum also depends on the location of the substitutional dopants: for single atom doping the largest transmission is obtained for edge substitutions, whereas substitutions in the middle of the sample give larger transmission for double carbon substitutions. The obtained results are explained in terms of electron localization in the system due to the presence of impurities.