Shaoxiong Lin

One-Pot Synthesis of Graphene-Supported Monodisperse Pd Nanoparticles as Catalyst for Formic Acid Electro-oxidation

To synthesize monodisperse palladium nanoparticles dispersed on reduced graphene oxide (RGO) sheets, we have developed an easy and scalable solvothermal reduction method from an organic solution system. The RGO-supported palladium nanoparticles with a diameter of 3.8 nm are synthesized in N-methyl-2-pyrrolidone (NMP) and in the presence of oleylamine and trioctylphosphine, which facilitates simultaneous reduction of graphene oxide and formation of Pd nanocrystals. So-produced Pd/RGO was tested for potential use as electrocatalyst for the electro-oxidation of formic acid. Pd/RGO catalyzes formic acid oxidation very well compared to Pd/Vulcan XC-72 catalyst. This synthesis method is a new way to prepare excellent electrocatalysts, which is of great significance in energy-related catalysis.

Sensitive detection of acetaminophen based on Fe3O4 nanoparticles-coated poly(diallyldimethylammonium chloride)-functionalized graphene nanocomposite film

An electrochemical sensor based on Fe(3)O(4) nanoparticles (NPs)-coated poly(diallyldimethylammonium chloride) (PDDA)-functionalized graphene (Fe(3)O(4)-PDDA-G) nanocomposite was fabricated for sensitive detection of acetaminophen. The nanocomposite was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). The electrochemical behaviors of acetaminophen on Fe(3)O(4)-PDDA-G composite film modified glassy carbon electrode (GCE) were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The experimental results indicated that the incorporation of Fe(3)O(4) NPs with PDDA-G greatly enhanced the electrochemical response of acetaminophen. This fabricated sensor displayed excellent analytical performance for acetaminophen detection over a range from 0.1 to 100 μ mol L(-1) with a detection limit of 3.7×10(-8) mol L(-1) (S/N=3). The redox peaks of acetaminophen, dopamine (DA) and ascorbic acid (AA) can be well separated on the Fe(3)O(4)-PDDA-G/GCE. Moreover, the proposed electrochemical sensor also exhibited good reproducibility and stability, and has been used to detect acetaminophen in tablets with satisfactory results.

Synthesis of PtAu bimetallic nanoparticles on graphene-carbon nanotube hybrid nanomaterials for nonenzymatic hydrogen peroxide sensor

PtAu bimetallic nanoparticles (NPs) were successfully synthesized on graphene sheets-multi walled carbon nanotubes (G-CNTs) hybrid nanomaterials via a simple one-step chemical co-reduction method in ethylene glycol (EG)-water system. The nanocomposites (PtAu/G-CNTs) were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Then a sensitive nonenzymatic hydrogen peroxide (H2O2) sensor was fabricated based on PtAu/G-CNTs nanocomposites modified glassy carbon electrode (GCE). The results of electrochemical experiments demonstrated that the sensor exhibited excellent electrocatalytic activity to the reduction of H2O2. The sensor displayed a fast amperometric response time of less than 4s with linear detection range from 2.0 to 8561 μM and a relatively low detection limit of 0.6 μM (S/N=3). In addition, the sensor also showed good selectivity for H2O2 detection, long-term stability and reproducibility.

Influence of reaction parameters on synthesis of high-quality single-layer graphene on Cu using chemical vapor deposition

Large-area monolayer graphene samples grown on polycrystalline copper foil by thermal chemical vapor deposition with differing CH4 flux and growth time are investigated by Raman spectra, scanning electron microscopy, atomic force microscopy, and scanning tunneling microscopy. The defects, number of layers, and quality of graphene are shown to be controllable through tuning the reaction conditions: ideally to 2–3 sccm CH4 for 30 minutes.