Controlling transport properties of graphene nanoribbons by codoping-induced edge distortions

TL;DR

This paper demonstrates that co-doping graphene nanoribbons with boron and nitrogen can systematically control their charge transport properties by inducing edge distortions, offering a new method to tune their electronic behavior.

Contribution

It introduces a novel co-doping strategy in armchair graphene nanoribbons to control transport properties through edge distortions, expanding beyond previous edge doping effects.

Findings

B/N co-doping induces donor-acceptor transition in aGNRs.

Co-doped aGNRs show improved conductance at valence or conduction band edges.

Edge distortions significantly influence the transport behavior.

Abstract

One notable manifestation of the peculiar edge-localized states in zigzag graphene nanoribbons (zGNRs) is the p-type (n-type) characteristics of nitrogen (boron) edge-doped GNRs, and such behavior was so far considered to be exclusive for zGNRs. Carrying out first-principles electronic structure and quantum transport calculations, we herein show that the donor-acceptor transition behavior can also arise in the B/N edge-doped armchair GNRs (aGNRs) by introducing a bipolar P codopant atom into the energetically most favorable nearest neighbor edge sites. The n-type (p-type) transport properties of B,P (N,P) co-doped aGNRs are also shown to be superior to those of reference single N (B) doped aGNRs in that the valence (conduction) band edge conductance spectra are better preserved. Disentangling the chemical doping and structural distortion effects, we will demonstrate that the latter plays an important role in determining the transport type and explains the donor-acceptor transition feature as well as the bipolar character of P-doped aGNRs. We thus propose the systematic modification of GNR edge atomic structures via co-doping as a novel approach to control charge transport characteristics of aGNRs.