# Synergistic Electronic Modulation in Nitrogen, Sulfur, and Boron-Doped Graphene Nanoribbons for Enhanced Oxygen Reduction Electrocatalysis

## TL;DR

This paper explores how doping graphene nanoribbons with nitrogen, sulfur, and boron improves their ability to catalyze oxygen reduction reactions, which is important for energy storage devices.

## Contribution

The study introduces a scalable method for creating metal-free electrocatalysts using synergistic electronic modulation via nitrogen, sulfur, and boron doping.

## Key findings

- NSB-GNR showed an onset potential of 0.805 V and a half-wave potential of 0.658 V for oxygen reduction.
- Boron incorporation induced defect reconstruction in the carbon lattice.
- Synergistic interactions among the dopants improved electrocatalytic performance despite reduced surface area.

## Abstract

The sluggish kinetics
of the oxygen reduction reaction (ORR) remains
one of the main challenges in the development of efficient and sustainable
metal-free catalysts for energy conversion and storage devices. Multielement
doping of carbon materials has emerged as an effective strategy to
tailor their electronic properties and enhance ORR activity. In this
study, graphene nanoribbons codoped with nitrogen, sulfur, and boron
(NSB-GNR) were prepared via a facile hydrothermal route, comprehensively
characterized and evaluated for ORR catalysis. Characterization by
EELS, FTIR, XPS, and ICP-OES confirmed successful heteroatom incorporation
and revealed that boron was mainly located in the inner layers of
NSB-GNR. Raman analysis suggested that boron incorporation may have
induced defect reconstruction within the carbon lattice. Nitrogen
adsorption–desorption and zeta potential analyses indicated
that the acidic environment generated by boric acid during hydrothermal
synthesis partially neutralized surface charges, leading to reduced
BET surface area (176 m2 g–1) and pore
volume (0.23 cm3 g–1) compared with the
N,S-doped counterpart. Despite this reduction, NSB-GNR exhibited superior
ORR performance with an onset potential of 0.805 V, half-wave potential
of 0.658 V vs RHE, and a limiting current density of −3.24
mA cm–2, following an efficient four-electron transfer
pathway. These findings demonstrate that the synergistic interactions
among nitrogen, sulfur, and boron dominate over textural effects,
providing new insights into the cooperative electronic modulation
of heteroatoms and offering a scalable strategy for designing advanced
metal-free carbon electrocatalysts.