A top-down synthesis of graphene quantum dots (GQD) was carried out by hydrothermal method from different carbon sources (graphene, multi-walled nanotubes, and black carbon) H2O2 as an oxidizing agent, with N source added in the reaction to modify chemical surface GQD, giving rise nanomaterial N-GQD. The modified N-GQD partially allowed nucleation coupling gold nanoparticles a HAuCl4 solution. ...

The hydrogenation of 4-nitrophenol (4-NP) has attracted much attention, since it is typically used as a model reaction for evaluating newly developed catalysts, but its mechanism still debated. Herein, Co(OH)2-modified CuO catalyst (Co(OH)2/CuO) was the reduction 4-NP to 4-aminophenol (4-AP) in an aqueous sodium borohydride (NaBH4) solution. investigated by UV-Vis spectroscopy (UV-Vis), high-pe...

Pure and doped magnesium oxide (MgO) thin films were prepared with different volumetric ratios (0, 2, 4, 6, 8%) of zinc sulfide (ZnS) on glass substrates at (350 °C) by chemical spray pyrolysis technique. The surface topography, absorption spectrum, coefficient Urbach energy the studied. atomic force microscopy (AFM) results revealed that topography changes as percentage doping increases. absor...

objective(s): silver nanoparticles (ag nps) are not only specific physical and chemical properties but also are considered for their antibacterial activity and ecofriendly.materials and methods:in this study a simple, cost effective biologically method for ag+reducing to ag nps using echinops extractas a stabilizer, and reducing agent.ag nps were analyzed using uv-vis spectrometry,tem, xrd and ...