Gai Yang

Bimetallic PtRu Nanoparticles Supported on Functionalized Multiwall Carbon Nanotubes as High Performance Electrocatalyst for Direct Methanol Fuel Cells

PtRu nanoparticles (NPs) supported on acid treated multiwall carbon nanotubes (Pt1Ru1/MWCNTs) were prepared by a modified polyol method without adding any other surfactant or protective agent. The structural and compositional properties of the as-obtained samples were characterized by transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and X-ray photoelectron (XPS) spectroscopy. The electrocatalytic performance of the catalyst was evaluated by cyclic voltammetry (CV), CO stripping voltammetry and chronoamperometry, indicating a high catalytic activity, excellent CO tolerance and stability for methanol oxidation. Interestingly, a series of accurate controllable experiments have been designed to explore the enhancement mechanism of Pt1Ru1/MWCNTs for methanol oxidation reaction. Most importantly, Pt1Ru1/MWCNTs composites were used as an anode catalyst in the direct methanol fuel cells (DMFCs) exhibiting outstanding power density (126.1 mW/cm2) 1.7 times hig...

The Material Performance of PA6 Modified with POE-g-MAH

The behavior of polyamide 6(PA6) toughened by maleic anhydride(MAH) grafting polyolefin elastomer(POE) were reported. The tensile strength, elongation at break, charpy impact strength and melt flow rate were studied in the experiments. The impact fracture surfaces were observed by scanning electron microscope (SEM). The results showed that the impact strength increased significantly when the content of POE-g-MAH has been reached 25%. From the SEM micrograph of impact fracture surface, it could be seen that there large amounts of crazing and microholes has been formed during the impact process, which caused the high toughness of PA6.

Preparation and performance of Nano-LiFePO4/C cathode material for lithium-ion battery

A high energy density LiFePO4/C material for lithium batteries was synthesized by controlled crystallization-carbothermal reaction, which has been experienced as an effective process for mass production of electrode materials. The structure and morphology of the LiFePO4/C material were characterized by X-ray diffraction and Scanning Electron Microscope (SEM). The electrochemical properties of the synthesized nano-LiFePO4/C were investigated by charge-discharge processing and cyclic voltammetry (CV). The initial discharge capacities of the LiFePO4/C battery were 163.9, 158.4, 154.5, 151.4, and 142 mA h g–1 at 0.1C, 1C, 2C, 5C, and 10C, respectively. The capacity of LiFePO4/C material maintained 98.5% at the rate of 1C after 100 cycles, demonstrating excellent rate capability and cycling performance.

Studies on the Properties of LiFePO4 -C/Li Batteries Doped Carbon by Vapor Deposition

A vapor deposed LiFePO4/C composite cathode material was acquired through filled carbon to FePO4 precursor by vapor deposition. The results showed that the carbon could contact to LiFePO4 nanopaticle directly and uniformly and formed a conducting network. It showed a good discharge capacity retention at large discharge rate. It was 57.3% at 10C. It also showed an excellent capacity steady characteristic when cycling at 1C.

A comparative study of the reactivity of three plant oil methyl esters with divinylbenzene by FTIR spectroscopy

Abstract Poly(divinylbenzene) microspheres were prepared by seed swelling polymerization of divinylbenzene in the presence of tung oil methyl esters, linseed oil methyl esters and soybean oil methyl esters, respectively. FTIR spectroscopy was used to characterize the polymers for investigating the reactivity of the three plant oil methyl esters. Results showed that tung oil methyl esters had strongest reactivity with divinylbenzene, and soybean oil methyl esters had weakest reactivity of the three oil methyl esters in the polymerization. These results were related with the fatty acid compositions of the oils.