Understanding of the optical/photocatalytic properties of bismuth oxyiodide with reduced graphene oxide

Abstract

Semiconductor photocatalysis has attracted great interest because it offers a promising approach to solving environmental aquatic pollution. This study comprehends a synthesis via the reflux method for obtaining Bismuth Oxyiodide (BiOI) and BiOI joined at reduced graphene oxide (BiOI/rGO). The materials were studied using different experimental and theoretical techniques including X-ray diffraction, N2 adsorption-desorption isotherms, SEM, TEM, Raman, DRS, and density functional theory calculations (DFT). The results indicated that BiOI/rGO has a crystal structure considerably stable, where interplanar spacing and the lattice parameters experienced only slight changes. Experimental and theoretical results show that electronic interaction between rGO sheet and BiOI reduced the band-gap, but in the case of DFT underestimation of band-gap values. DFT analysis showed the role of the hydroxyl group and epoxy groups in the charge transfer along the interfacial direction of heterostructure BiOI/rGO. The adsorption-photocatalytic ability of BiOI/rGO was 2.5 times higher than the pristine BiOI. This study underscores the importance of material design in enhancing photocatalytic applications, paving the way for further research into similar composites for environmental remediation. The developed material will provide a novel strategy to facilitate the treatment of polluted waters in modern environmental engineering. © 2025 The Authors