Structural and optical properties of Fe3O4@Au/rGO nanocomposites synthesized by hydrothermal method and their photothermal effect under NIR laser irradiation

Abstract

One of the most promising methods of heat generation is using the nanosources, as absorbent light, under near-infrared (NIR) irradiation. Here, the Fe3O4@Au/rGO nanocomposites (NCs) with various graphene content (10, 25, and 40 wt%) synthesized by hydrothermal reaction method. The heat generated by Fe3O4@Au/rGO NCs suspensions under NIR laser irradiation (808 nm) in various concentration and times has been experimentally determined. The physical characteristics of these nanocomposite were studied using FE-SEM, TEM, XRD, XPS, FTIR, UV–vis, and Raman techniques. TEM and FE-SEM images displayed the spherical shape of Fe3O4@Au NCs which had varying diameter from 20 to 30 nm, coated to rGO sheets (with ~1 μm lateral dimension). The results demonstrate that the temperature of suspension under NIR laser irradiation raises from 5 to 40 °C with the increase of both the graphene contents and concentration. The Fe3O4@Au/rGO NCs are proposed as promising nanosources for heat generation under NIR laser irradiation and are useful for photothermal therapy, biomedical imaging, photothermal imaging, catalysis, and sensors applications.