Cadmium oxide nanoparticles grown in situ on reduced graphene oxide for enhanced photocatalytic degradation of methylene blue dye under ultraviolet irradiation

• CdO NPs are nicely decorated over the rGO sheets by in-situ hydrothermal method.
• CdO NPs on rGO sheets with visible wrinkles suggest that the rGO sheets are composed of only few layers.
• rGO-CdO nanocomposites show enhanced photocatalytic activity for the photodegradation of MB dye.
• The rGO-CdO nanocomposites exhibit RTFM.

Cadmium oxide (CdO) nanoparticles (NPs), reduced graphene oxide (rGO) and rGO-CdO nanocomposites have been synthesized using one step hydrothermal method. The structural and optical properties of CdO NPs, rGO, and rGO-CdO nanocomposites were investigated by X-ray diffraction (XRD), energy dispersive X-ray (EDX), high resolution transmission electron microscopy (HR-TEM), Raman spectroscopy (RS), ultraviolet–visible spectroscopy (UV–Vis.) and photoluminescence (PL) spectroscopy techniques. The rGO has a sharp 2D peak compared to GO. The sharp nature of 2D band may be due to the larger contribution from single layer sheet. The photocatalytic activity of the synthesized samples has been investigated under UV irradiation. The results of photocatalytic measurements revealed that ~ 80% of MB dye is degraded by adding the rGO-CdO nanocomposites as photocatalysts into the dye solution. The decrease in the intensity of emission peaks indicates that the photogenerated charge carriers have been transferred from CdO NPs to rGO sheets, which causes to increase the density of O2− and OH radicals in the dye solution. The CdO nanoparticles gown on the rGO sheets showed enhanced ferromagnetism (FM) at room temperature, which may be attributed to the short range magnetic interaction of magnetic moments of CdO NPs and spin units present on the rGO sheets.

One pot in-situ hydrothermal method provides a facile and easy approach to decorate well dispersed, stable and ferromagnetic CdO NPs on rGO sheets. The photocatalytic activity of pure CdO NPs on MB dye is enhanced due to delay in recombination time of e−–h+ pairs by incorporation of rGO sheets.Figure optionsDownload as PowerPoint slide