Synthesis of High-Quality Graphene through Electrochemical Exfoliation of Graphite in Alkaline Electrolyte

TL;DR

This paper presents a cost-effective electrochemical method using alkaline electrolyte to synthesize high-quality, few-layer graphene with minimal defects, suitable for various applications.

Contribution

It introduces a novel alkaline electrochemical exfoliation process that avoids damaging oxidation, producing large, high-quality graphene with nearly absent disorder.

Findings

Graphene with 1-4 layers and large lateral size (~18 μm) was produced.

Raman analysis shows absence of D peak, indicating low disorder.

The method is simple, economical, and preserves graphene quality.

Abstract

Owing to wide variety of applications of graphene, high-quality and economical way of synthesizing graphene is highly desirable. In this study, we report a cost effective and simple approach to production of high-quality graphene. Here the synthesis route is based on electrochemical exfoliation of graphite. Instead of using strong acids (which oxidise and damage the geometrical topology of graphene), we have used alkaline solution (KOH dissolved in water) as electrolyte. TEM analysis shows that as prepared graphene has 1-4 layers and large lateral size (up to ~18 micrometer). Raman analysis shows a unique feature. The D peak which is invariably present in graphene is absent here. This suggests that disorder in the graphene sheets synthesized by the present method, is nearly absent. A tentative mechanism of electrochemical exfoliation in alkaline electrolyte is discussed and described.