An Overview of Graphene-Based 2D/3D Nanostructures for Photocatalytic Applications

Photocatalytic processes induced by inexhaustible solar energy have fascinated significant research to solve issues like energy crisis and environmental pollution since they possess several merits, like renewable energy sources, safety and low operating cost. Photocatalysis is also considered as one of the environment-friendly sustainable methods for the degradation of organic contaminants. The conversion of CO 2 into hydrocarbon fuel with low energy via photocatalytic reduction is another application of this field that can realize the efficient conversion and storage of solar energy to chemical energy and the recycling of carbon in practical applications. Furthermore, this clean technique is commonly employed in water treatment, bacteria disinfection, and selective organic compound synthesis. The graphene-based two-dimensional (2D) and three-dimensional (3D) nanostructures can solve many issues of using conventional photocatalysts; due to their versatile properties, including peculiar morphology, surface area, stability, optical adsorption, electrical, electrochemical and photoelectrochemical properties. The main highlight for the graphene-based structures is the synergism between the adsorption and photocatalytic activity in removing organic pollutants. This review mainly presents an overview of the processes/mechanisms and evolution strategies for developing graphene-based 2D/3D nanostructured systems. Various applications of graphene-based heterostructured photocatalysts were also detailed. The ongoing challenges and significant state-of-the-art advances on graphene-based systems are also discussed in this review.