In-situ growth, and potent photocatalytic performance of gold-decorated reduced graphene oxide (Au/rGO): A soft nanocomposite material

•Controlled synthesis of Au/rGO in accordance with Hummer's approach.•Comprehensive physiochemical analysis to assess its efficacy as a photo-catalyst.•Au/rGO: Effective Organic Contaminant Absorber; Chunks electron-hole pair recombination. The investigation focuses on the phenomenon of in-situ growth of gold-decorated reduced graphene oxide (Au/rGO) nanocomposites and its applications as a highly efficient photo-catalyst in the realm of mitigating environmental pollutants. In order to explore the degrading impact of rGO, rGO decorated with gold nanoparticles (Au/rGO) was successfully synthesized via a chemical reduction technique. The purity and functional characteristics of as-grown Au/rGO nanostructures were ascertained by structural, morphological, elemental, and optical investigation. Analysis of the acquired XRD pattern, FTIR and Raman spectra, and SEM and TEM images demonstrated the successful preparation of rGO and its decoration with Au nanoparticles. Moreover, under UV–VIS light, the as-prepared nanocomposite (Au/rGO) was employed as a photocatalyst for the degradation of a selected organic pollutant, methyl orange (MO) dye. The ‘Langmuir-Hinshelwood (L-H) model’ has been effectively used to show that the exposure of a surface monolayer to light causes MO dye molecules to adsorb. The mechanism and kinetics of the MO elimination approach suggest that pseudo-second-order kinetics are most accurately followed and described. The maximal photodegradation rates for MO dye using Au/rGo and rGO nanocomposite were determined to be 92% and 64%, respectively, in the same 45-minute time frame. The improved photocatalytic activity of Au/rGO was proposed to be caused by the effective suppression of electron-hole recombination by the rGO on the Au nanoparticles. Hence, the results suggest that graphene decorated with gold yields a more efficient photocatalyst for environmental applications. One of the novel aspects of this study lies in the proficiently managed synthesis of Au/rGO and its prospective applications as a photo- catalyst for environmental pollution such as to remove pollutants from water.