Graphene is a two-dimensional nanomaterial with exceptionally interesting physical and chemical properties, which has been actively explored in nanoelectronics, nanodevices and nanoscale catalysis. Here we report a graphene-templated route toward mild, solution-phase synthesis of ultrathin single crystal lepidocrocite (γ-FeOOH) nanosheets with high aspect ratio. We find that when reduced graphene oxide (rGO) was incubated with FeCl3 of 20 wt% at 80 °C and in the presence of reducing reagents (e.g.hydrazine hydrate), close-spaced 2D nanosheets of γ-FeOOH was formed on the surface of rGO, with the average thickness of 2.1 nm. This ultrathin nanomaterial was characterized via a range of complementary techniques, transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Mössbauer spectroscopy and synchrotron-based scanning transmission X-ray microscopy (STXM), which confirmed the formation of γ-FeOOH 2D nanosheets. Importantly, we explore the application of this novel nanomaterial as an efficient and stable catalyst for phenol treatment in wastewater.
The Shanghai Synchrotron Radiation Facility (SSRF) is the first third-generation synchrotron facility in China and operated at an electron energy of 3.5 GeV. One of the seven beamlines in the first construction phase is devoted to soft x-ray spectromicroscopy and is equipped with an elliptically polarized undulator light source, a plane grating monochromator, and a scanning transmission x-ray microscope end station. Initial results reveal the high performance of this beamline, with an energy resolving power estimated to be over 10 000 at the argon L-edge and a spatial resolution better than 30 nm.