Cathodic Exfoliation of Various Graphite Materials in Potassium Chloride Electrolyte

Cathodic exfoliation of graphite has emerged as an attractive method to synthesize high-quality and lo- defect graphene. Here, it is demonstrated that the type of starting graphite material influences the properties of exfoliated graphene. Graphite foil, natural graphite, and graphite rods were exam...

Full description

Saved in:
Bibliographic Details
Main Authors: Md Habibullah Dalal, Nuwan Hegoda Arachchi, Chong-Yong Lee, Gordon G. Wallace
Format: Article
Language:English
Published: MDPI AG 2025-07-01
Series:Molecules
Subjects:
Online Access:https://www.mdpi.com/1420-3049/30/15/3151
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849406090231414784
author Md Habibullah Dalal
Nuwan Hegoda Arachchi
Chong-Yong Lee
Gordon G. Wallace
author_facet Md Habibullah Dalal
Nuwan Hegoda Arachchi
Chong-Yong Lee
Gordon G. Wallace
author_sort Md Habibullah Dalal
collection DOAJ
description Cathodic exfoliation of graphite has emerged as an attractive method to synthesize high-quality and lo- defect graphene. Here, it is demonstrated that the type of starting graphite material influences the properties of exfoliated graphene. Graphite foil, natural graphite, and graphite rods were examined in the exfoliation processes performed in 3.0 M KCl at −15 V. The use of a graphite foil facilitates the rapid cathodic exfoliation process in comparison with structurally more compact natural graphite and graphite rods. For the graphite foil, the cathodically exfoliated graphene exhibits a low defect density (<i>I</i><sub>D</sub>/<i>I</i><sub>G</sub> of 0.09, a C/O ratio of 35) with graphite exfoliation yield of 92.8%. In contrast, the exfoliated graphene from natural graphite exhibits an <i>I</i><sub>D</sub>/<i>I</i><sub>G</sub> of 0.15, a C/O ratio of 28, and a graphite exfoliation yield of 30.5%, whereas graphene from graphite rod exhibits an <i>I</i><sub>D</sub>/<i>I</i><sub>G</sub> of 0.86, a C/O ratio of 30, and a graphite exfoliation yield of 19.5%. The dense structure of natural graphite and graphite rods led to longer exfoliation times. Exfoliation of graphite rods produced few-layer graphene with the smallest sheet size, whereas natural graphite and graphite foil yielded multilayer graphene with larger sheets. This study demonstrates the feasibility of using aqueous-based cathodic exfoliation to produce graphene from various graphite sources, leading to variations in sheet thickness, size, defect density, and solvent dispersibility.
format Article
id doaj-art-0ce22b2b234d450fa7566ecc0010f070
institution Kabale University
issn 1420-3049
language English
publishDate 2025-07-01
publisher MDPI AG
record_format Article
series Molecules
spelling doaj-art-0ce22b2b234d450fa7566ecc0010f0702025-08-20T03:36:31ZengMDPI AGMolecules1420-30492025-07-013015315110.3390/molecules30153151Cathodic Exfoliation of Various Graphite Materials in Potassium Chloride ElectrolyteMd Habibullah Dalal0Nuwan Hegoda Arachchi1Chong-Yong Lee2Gordon G. Wallace3Intelligent Polymer Research Institute, AIIM Facility, Faculty of Engineering and Information Science, University of Wollongong, Wollongong, NSW 2500, AustraliaIntelligent Polymer Research Institute, AIIM Facility, Faculty of Engineering and Information Science, University of Wollongong, Wollongong, NSW 2500, AustraliaIntelligent Polymer Research Institute, AIIM Facility, Faculty of Engineering and Information Science, University of Wollongong, Wollongong, NSW 2500, AustraliaIntelligent Polymer Research Institute, AIIM Facility, Faculty of Engineering and Information Science, University of Wollongong, Wollongong, NSW 2500, AustraliaCathodic exfoliation of graphite has emerged as an attractive method to synthesize high-quality and lo- defect graphene. Here, it is demonstrated that the type of starting graphite material influences the properties of exfoliated graphene. Graphite foil, natural graphite, and graphite rods were examined in the exfoliation processes performed in 3.0 M KCl at −15 V. The use of a graphite foil facilitates the rapid cathodic exfoliation process in comparison with structurally more compact natural graphite and graphite rods. For the graphite foil, the cathodically exfoliated graphene exhibits a low defect density (<i>I</i><sub>D</sub>/<i>I</i><sub>G</sub> of 0.09, a C/O ratio of 35) with graphite exfoliation yield of 92.8%. In contrast, the exfoliated graphene from natural graphite exhibits an <i>I</i><sub>D</sub>/<i>I</i><sub>G</sub> of 0.15, a C/O ratio of 28, and a graphite exfoliation yield of 30.5%, whereas graphene from graphite rod exhibits an <i>I</i><sub>D</sub>/<i>I</i><sub>G</sub> of 0.86, a C/O ratio of 30, and a graphite exfoliation yield of 19.5%. The dense structure of natural graphite and graphite rods led to longer exfoliation times. Exfoliation of graphite rods produced few-layer graphene with the smallest sheet size, whereas natural graphite and graphite foil yielded multilayer graphene with larger sheets. This study demonstrates the feasibility of using aqueous-based cathodic exfoliation to produce graphene from various graphite sources, leading to variations in sheet thickness, size, defect density, and solvent dispersibility.https://www.mdpi.com/1420-3049/30/15/3151cathodic exfoliationgraphenegraphite sourcesdegree of graphitization
spellingShingle Md Habibullah Dalal
Nuwan Hegoda Arachchi
Chong-Yong Lee
Gordon G. Wallace
Cathodic Exfoliation of Various Graphite Materials in Potassium Chloride Electrolyte
Molecules
cathodic exfoliation
graphene
graphite sources
degree of graphitization
title Cathodic Exfoliation of Various Graphite Materials in Potassium Chloride Electrolyte
title_full Cathodic Exfoliation of Various Graphite Materials in Potassium Chloride Electrolyte
title_fullStr Cathodic Exfoliation of Various Graphite Materials in Potassium Chloride Electrolyte
title_full_unstemmed Cathodic Exfoliation of Various Graphite Materials in Potassium Chloride Electrolyte
title_short Cathodic Exfoliation of Various Graphite Materials in Potassium Chloride Electrolyte
title_sort cathodic exfoliation of various graphite materials in potassium chloride electrolyte
topic cathodic exfoliation
graphene
graphite sources
degree of graphitization
url https://www.mdpi.com/1420-3049/30/15/3151
work_keys_str_mv AT mdhabibullahdalal cathodicexfoliationofvariousgraphitematerialsinpotassiumchlorideelectrolyte
AT nuwanhegodaarachchi cathodicexfoliationofvariousgraphitematerialsinpotassiumchlorideelectrolyte
AT chongyonglee cathodicexfoliationofvariousgraphitematerialsinpotassiumchlorideelectrolyte
AT gordongwallace cathodicexfoliationofvariousgraphitematerialsinpotassiumchlorideelectrolyte