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N-Graphene Nanowalls via Plasma Nitrogen Incorporation and Substitution: The Experimental Evidence.

ABSTRACT: Incorporating nitrogen (N) atom in graphene is considered a key technique for tuning its electrical properties. However, this is still a great challenge, and it is unclear how to build N-graphene with desired nitrogen configurations. There is a lack of experimental evidence to explain the influence and mechanism of structural defects for nitrogen incorporation into graphene compared to the derived DFT theories. Herein, this gap is bridged through a systematic study of different nitrogen-containing gaseous plasma post-treatments on graphene nanowalls (CNWs) to produce N-CNWs with incorporated and substituted nitrogen. The structural and morphological analyses describe a remarkable difference in the plasma-surface interaction, nitrogen concentration and nitrogen incorporation mechanism in CNWs by using different nitrogen-containing plasma. Electrical conductivity measurements revealed that the conductivity of the N-graphene is strongly influenced by the position and concentration of C-N bonding configurations. These findings open up a new pathway for the synthesis of N-graphene using plasma post-treatment to control the concentration and configuration of incorporated nitrogen for application-specific properties.

SUBMITTER: M Santhosh N

PROVIDER: S-EPMC7770896 | biostudies-literature |

REPOSITORIES: biostudies-literature

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