Non-Enzymatic H2O2 Sensor Using Liquid Phase High-Pressure Exfoliated Graphene

Importance of graphene-based nanomaterials in electrochemical sensors has increased due to their exceptional electrochemical properties and electrocatalytic activity. Despite the significant amount of work on graphene exfoliation, there is a need for large-scale, environmental friendly production of high-quality graphene for electrochemical sensing applications. This work describes the use of liquid phase mechanical (high-pressure) exfoliation for synthesis of graphene and its application in H2O2 electrochemical sensors. The basic electrochemical characterizations of exfoliated graphene samples have shown great enhancement in electrochemical activity due to their improved ion adsorption ability as a result of increased electroactive surface area and the presence of functional groups (defective sites). The developed H2O2 sensors showed excellent sensitivity and limit of detection (LOD). The repeatability, reproducibility, and stability studies of liquid phase mechanical exfoliated graphene-based H2O2 sensors showed consistent results suggesting the potential usage of the exfoliated graphene in electrochemical sensors. The interference study of fabricated sensors revealed the selective H2O2 sensing nature of exfoliated graphene and confirmed its potential for H2O2 determination in real samples.