Zhao Qing University

Zhaoqing, China

Zhao Qing University

Zhaoqing, China
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Wu Y.-N.,University of California at Riverside | Guo H.-F.,Zhao Qing University | Hu P.,Zhao Qing University | Xiao X.-P.,Zhao Qing University | And 2 more authors.
Nano | Year: 2016

Three types of ternary low-platinum nanocatalysts, alloy PdPtIr/C, core–shell PdPt@PtIr/C and Pd@PtIr/C, have been prepared, and their catalytic behaviors toward methanol oxidation reaction (MOR)/oxygen reduction reaction (ORR) are comparatively investigated via cyclic voltammetry and chronoamperometry analysis in an acidic medium. Through a two-step colloidal technique, the synthesized core–shell structured catalyst PtPd@PtIr/C with alloy core and alloy shell show the best catalytic activity toward MOR and the best poisoning tolerance. The alloy PdPtIr/C catalyst prepared via a one-step colloidal technique exhibits the best performance toward ORR among the three catalysts. All the three catalysts are characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and other characterization techniques. © 2016 World Scientific Publishing Company


Wu Y.-N.,South China University of Technology | Wu Y.-N.,Zhao Qing University | Liao S.-J.,South China University of Technology | Su H.-N.,South China University of Technology | And 2 more authors.
Fuel Cells | Year: 2010

Carbon nanotubes (CNTs) were shortened from 5 to 15 μm to ca. 200 nm using ball milling with ethanol as the milling aid agent, and a platinum catalyst with these shortened carbon nanotubes (SCNTs) as the support was prepared by a high-pressure colloidal method. It was found that this catalyst with SCNTs showed much higher activity than a platinum catalyst with normal CNTs as support; for methanol anodic oxidation, the activity of the Pt/SCNTs was 50% higher than that of the Pt/CNTs, and the Pt/SCNTs also showed higher activity for the cathodic reduction of oxygen. The Pt/SCNTs were characterised by X-ray diffraction scanning and transmission electron microscropy. It is suggested that the significant performance enhancement when SCNTs are used as support might result from the generation of new surfaces and defects, the opening of closed nanotubes in the process of milling, higher platinum dispersion on the shortened nanotubes and the interaction of platinum nanoparticles with the SCNTs. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Wu Y.-N.,Zhao Qing University | Wu Y.-N.,South China University of Technology | Liao S.-J.,South China University of Technology | Zeng J.-H.,South China University of Technology
Journal of Power Sources | Year: 2011

Small nanoparticles offer high surface areas and are certainly desirable for electrocatalytic reactions and fuel cells. However, the drawback of using small nanoparticles is their tendency towards particle aggregation. This paper aims to inhibit platinum agglomeration by adding silicon oxide to a carbon support for enhanced catalytic activity in low-temperature fuel cells. The catalysts are characterized by X-ray diffraction and transmission electron microscopy. Physical characterization and cyclic voltammetry techniques at room temperature are used to assess the effects of silicon oxide amount, post-heating temperature, and holding time on particle size and dispersion of active components, and the catalysts' activity towards the methanol oxidation and oxygen reduction reactions. It is found that using a support of carbon powder with 3 wt.% silicon oxide can enhance the electrochemically active surface area of Pt catalysts and their activity towards the anodic oxidation of methanol and reduction of oxygen. The active components are also more resistant than Pt/C to agglomeration upon heating. © 2010 Elsevier B.V.


Wu Y.N.,South China University of Technology | Wu Y.N.,Zhao Qing University | Liao S.J.,South China University of Technology | Su Y.L.,CAS Institute of Chemistry | And 2 more authors.
Journal of Power Sources | Year: 2010

A palladium decorated Pt/C catalyst, Pt@Pd/C, is prepared by a colloidal approach with a small amount of platinum as core. It is found that the catalyst shows excellent activity towards anodic oxidation of formic acid at room temperature and its activity is 60% higher than that of Pd/C. Decoration of palladium shell on the platinum core is supported by XPS results. Due to the use of platinum as core, active components are dispersed very well and the particle sizes are smaller than those of Pd/C. The cyclic voltammetry measurement clearly shows synthetic electro-oxidation effects of formic acid on Pt@Pd/C. It is speculated that the high performance of Pt@Pd/C may result from the unique core-shell structure and synergistic effect of Pt and Pd at the interface. The preparation method for Pt@Pd/C reported in this work will provide additional options for the design of catalysts for direct formic acid fuel cell (DFAFC). © 2010 Elsevier B.V. All rights reserved.


Mo Z.,South China University of Technology | Mo Z.,Zhao Qing University | Zheng R.,South China University of Technology | Peng H.,South China University of Technology | And 2 more authors.
Journal of Power Sources | Year: 2014

Well defined nitrogen-doped graphene (NG) is prepared by a transfer doping approach, in which the graphene oxide (GO) is deoxidized and nitrogen doped by the vaporized polyaniline, and the GO is prepared by a thermal expansion method from graphite oxide. The content of doped nitrogen in the doped graphene is high up to 6.25 at% by the results of elements analysis, and oxygen content is lowered to 5.17 at%. As a non-precious metal cathode electrocatalyst, the NG catalyst exhibits excellent activity toward the oxygen reduction reaction, as well as excellent tolerance toward methanol. In 0.1 M KOH solution, its onset potential, half-wave potential and limiting current density for the oxygen reduction reaction reach 0.98 V (vs. RHE), 0.87 V (vs. RHE) and 5.38 mA cm -2, respectively, which are comparable to those of commercial 20 wt% Pt/C catalyst. The well defined graphene structure of the catalyst is revealed clearly by HRTEM and Raman spectra. It is suggested that the nitrogen-doping and large surface area of the NG sheets give the main contribution to the high ORR catalytic activity. © 2013 Elsevier B.V. All rights reserved.


Zheng R.,South China University of Technology | Mo Z.,South China University of Technology | Mo Z.,Zhao Qing University | Liao S.,South China University of Technology | And 3 more authors.
Carbon | Year: 2014

High-performance heteroatom-doped carbon catalysts with large surface areas were prepared by pyrolyzing nanorod precursors that had been synthesized by polymerizing a mixture of aniline (An) and β-naphthalene sulfonic acid (NSA). The catalysts were characterized by scanning and transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, N2 adsorption/desorption isotherms, and elemental analysis. We intensively investigated how the catalysts' structure and catalytic performance were affected by (i) the ratio of NSA to An and (ii) the addition of Fe. The catalysts retained their nanorod morphology after pyrolysis. The optimal NSA/An ratio was 3/2 and the optimal Fe content was 3 wt%. The catalysts showed excellent activity toward oxygen reduction in an acidic medium, with the onset potential, half-wave potential, and limiting current density values reaching 0.86, 0.73 V (vs. reversible hydrogen electrode), and 5.28 mA cm-2, respectively. We suggest that the catalysts' high performance may be due to the co-doping effects of nitrogen, sulfur, and iron, as well as the large surface area created by the nanorod structures. © 2013 Elsevier Ltd. All rights reserved.


Wu Y.-N.,Zhao Qing University | Liao S.-J.,South China University of Technology | Guo H.-F.,Zhao Qing University | Hao X.-Y.,Zhao Qing University
Journal of Power Sources | Year: 2013

A high-performance, low platinum loading catalyst for the anodic oxidation of methanol, Pd@PtRu/C, is prepared by a two-step colloidal approach. The activity of the Pd@PtRu/C catalyst is 1.67 times and 1.81 times that of PtRu/C and PtRuPd/C catalysts, respectively. The catalysts are characterized by TEM, XPS, and XRD. The active components are dispersed on the surface of the carbon support very well, yielding a particle size of ca. 4.7 nm and a shell thickness of ca. 0.25 nm. The catalyst's high activity may be attributed to the high exposure and dispersion of PtRu, as well as the interaction of PtRu in the shell layer with Pd in the core, resulting from the catalyst's core-shell structure. © 2012 Elsevier B.V. All rights reserved.


Wu Y.-N.,Zhao Qing University | Liao S.-J.,South China University of Technology | Guo H.-F.,Zhao Qing University | Hao X.-Y.,Zhao Qing University
Journal of Power Sources | Year: 2013

Shortened carbon nanotubes (SCNTs) obtained by ball milling of carbon nanotubes (5-10 μm) with the assistance of ethanol are used as supports for fabrication of core-shell structured PdPt@Pt/SCNTs via a successive colloidal reduction approach. The catalysts are characterized by X-ray diffraction (XRD) analysis, Transmission electron microscopy, and X-ray photoelectron spectroscopy. The active particles are found to disperse on the shortened carbon nanotubes with an average particle size of 3.1 nm. PtPd nanoparticles, rather than single Pd nanoparticles, are used as core materials for prevention of possible agglomeration and better dispersion. Using this catalyst, we investigate methanol oxidation reactions (MOR) and oxygen reduction reactions (ORR). The catalysts show excellent activity to anodic MOR, 2.87 times higher than that of commercial Johnson Matthey 40 wt.% Pt/C catalyst. The ratio of forward current Ifto backward current Ib is as high as 1.41 for the oxidation of methanol relative to that of 0.74 for the commercial Pt/C catalyst, an indication of better CO tolerance of the former. In the ORR, the reaction is found to proceed via an overall four-electron transfer process. © 2013 Elsevier B.V. All rights reserved.


Chen Y.,Zhao Qing University | Zhou Y.,Zhao Qing University | Cui H.,Zhao Qing University
WIT Transactions on Information and Communication Technologies | Year: 2014

The article reviews the traditional technology of integration and development of WebGIS and introduces a new kind of technology of integration and development of WebGIS using Web Service and XML (Extensible Markup Language) in.NET platform. Pointing out that establishes road traffic accident and rescues the systematic necessity in the urban area of Zhao Qing, rescue systematic structure, function, and workflow. © 2014 WIT Press.


Huan G.A.,Zhao Qing University | Hui P.P.,South China University of Technology | Jiang C.,South China University of Technology | Ru Y.Z.,South China University of Technology
Advanced Materials Research | Year: 2012

Aluminum sheet was encapsulated by inorganic-organic hybrid film through a base catalyzed sol-gel method using organic acrylate silane resin PMBV and TEOS as precursors. FTIR and AFM characterizations prove that PMBV and TEOS have hydrolyzed and co-condensed with each other in the sol-gel process to form an uniform film on the surface of aluminum sheet. XPS result shows hydroxyl groups on aluminum surface have taken part in the co-condensation reaction.

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