Construction of Nitrogen-Doped Carbon Nanosheets for Efficient and Stable Oxygen Reduction Electrocatalysis

Abstract

Two-dimensional nitrogen-doped carbon nanosheets (GCNS) have been fabricated through polymerization and carbonization using resorcinol, formaldehyde, aniline and graphene oxide as reactants. Herein, aniline serves as a nitrogen source for doping and graphene oxide is employed as the structure directing agent for nanosheet generation to engineer the structure. The resultant GCNS display a high surface area of 351 m 2 g À1 and N doping content of 1.06 wt.%. Moreover, the obtained electrocatalysts demonstrate superior electrocatalytic oxygen reduction characteristics with an onset potential of 0.920 V versus reversible hydrogen electrode, diffusion-limiting current density (À 4.24 mA cm À2) and improved stability in an alkaline medium. The optimized oxygen reduction performance can be attributed to the rapid mass transfer and abundant active sites owing to the synergistic coupling effects arising from heteroatom dopants and structure modulation. On one hand, heteroatom doping provides enhance electronic conductivity with abundant defects and effective charge diffusion with improved surface wettability, which favors the electrocatalytic performances. On the other hand, the unique two-dimensional structure of the resultant GCNS provides good electrolyte accessibility and short ion/electron diffusion distances. This work demonstrates an effective construction of targeted heteroatom doping carbon nanosheets with surface functionalities and structure modification as carbonbased catalysts with advanced electrocatalytic performances.

Comprehensive Review on Nitrogen-Doped Graphene: Structure Characterization, Growth Strategy, and Capacitive Energy Storage

“…(a) Schematic of the arc discharge apparatus (the inset illustrates the process in which the carbon material of the graphite anode is injected into the discharge core via vaporization). This panel was reproduced with permission from ref . Copyright 2021 Springer Nature.…”

“…The arc discharge method (Figure 6a) refers to use an electric current to bombard graphite electrodes under an atmosphere containing nitrogen precursors (pyridine, NH 3 , N 2 , etc.). 50 Panchakarla et al 51 used pyridine and ammonia to prepare NG with nitrogen contents of 0.6−1.4 atomic % under the protection of H 2 and He. Doping N contributed to higher conductivity and n-type semiconducting behavior (Figure 6b).…”

Diamond-Like Carbon (DLC) Coatings : Classification, Properties, and Applications

“…Meanwhile, the facile synthesis approach is arranged in such a way for three-dimensional (3D) N-doped C with a selected sp3/sp2 interface, which is derived from ionic liquids through shift transformation [38]. However, density functional theory reveals improved performance of ORR, and it can be ascribed to the existence of N dopants at the sp3/sp2 C interface [39,40,41,42,43,44,45].…”