The promise of graphene-based photocatalytic materials for wastewater remediation: A scoping review

Abstract

Graphene-based nanomaterials have attracted considerable interest for their outstanding performance in the photocatalytic degradation of environmental pollutants. This is primarily due to their high surface area, excellent electrical conductivity, and chemical stability. This review provides a comprehensive analysis of recent developments in the design, synthesis, and application of graphene and graphene oxide in photocatalysis. Key characterization techniques, including SEM, TEM, XRD, Raman spectroscopy, and UV–Vis absorption spectroscopy, are discussed to assess the structural and electronic features that influence photocatalytic performance.

Graphene-based photocatalysts have demonstrated effective degradation of a wide range of pollutants, including pharmaceutical residues like tetracycline and ibuprofen, endocrine-disrupting chemicals such as bisphenol A and phthalates, and industrial contaminants like dyes, phenols, and polycyclic aromatic hydrocarbons (PAHs), especially under visible light irradiation. The review highlights advancements in hybrid composites, surface functionalization, and heterostructures that enhance light absorption, charge carrier separation, and reactive oxygen species (ROS) generation. Despite their potential, several challenges hinder practical application, including high production costs, agglomeration tendencies, limited long-term reusability, and concerns about environmental toxicity in aquatic systems. To overcome these issues, recent innovations have focused on scalable synthesis techniques such as flash joule heating and the use of biomass-derived carbon sources. Furthermore, combining graphene with materials such as g-C₃N₄, MOFs, and doped semiconductors has significantly improved visible-light-driven photocatalytic efficiency. This review underscores the need for further development in recyclability and environmental safety. Graphene-based nanomaterials are emerging as promising candidates for next-generation solar-driven water purification and environmental remediation systems.