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Mandi Bahāuddīn, Pakistan

Tan W.,KTH Royal Institute of Technology | Tan W.,Nanjing Institute of Technology | Fan L.,KTH Royal Institute of Technology | Raza R.,KTH Royal Institute of Technology | And 4 more authors.
International Journal of Hydrogen Energy | Year: 2013

In this work, the effect of copper, iron and cobalt oxides on electrochemical properties of lithiated NiO cathodes was reported in low temperature solid oxide fuel cell (LT-SOFC) with ceria-carbonate composite electrolyte. The modified lithiated NiO cathodes were characterized by XRD, DC conductivity, SEM and electrochemical measurements. In spite of lower conductivities of modified cathodes, Li-Ni-M (M = Cu, Fe, Co) oxides with the order of Li-Ni-Co oxide > Li-Ni-Fe oxide > Li-Ni-Cu oxide, compared with that without modification, the catalytic activities of all the Li-Ni-M oxides were improved. In particularly, cobalt oxide modification favors both charge transfer and gas diffusion for O2 reduction reaction as confirmed by AC impedance measurements. SEM micrographs show that grains aggregate with the modification of copper oxide or iron oxide, which may be responsible for the increased gas diffusion resistance. The results indicate that the lithiated NiO modified by cobalt oxide as cathode is an alternative to improve LT-SOFC performance with ceria-carbonate composite electrolyte. © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source


Raza R.,KTH Royal Institute of Technology | Raza R.,COMSATS Institute of Information Technology | Abbas G.,COMSATS Institute of Information Technology | Abbas G.,Bahauddin Zakaria University | And 4 more authors.
Solid State Ionics | Year: 2011

The purpose of this study is to develop new oxide ionic conductors based on nanocomposite materials for an advanced fuel cell (NANOCOFC) approach. The novel two phase nanocomposite oxide ionic conductors, Ce0.8Sm 0.2O2 - δ (SDC)-Y2O3 were synthesized by a co-precipitation method. The structure and morphology of the prepared electrolyte were investigated by means of X-ray diffraction (XRD) and high resolution scanning electron microscopy (HRSEM). XRD results showed a two phase composite consisting of yttrium oxide and samaria doped ceria and SEM results exhibited a nanostructure form of the sample. The yttrium oxide was used on the SDC as a second phase. The interface between two constituent phases and the ionic conductivities were studied with electrochemical impedance spectroscopy (EIS). An electrochemical study showed high oxide ion mobility and conductivity of the Y2O3-SDC two phase nanocomposite electrolytes at a low temperature (300-600 °C). Maximum conductivity (about 1.0 S cm-1) was obtained for the optimized Y2O 3-SDC composite electrolyte at 600 °C. It is found that the nanocomposite electrolytes show higher conductivities with the increased concentration of yttrium oxides but decreases after reaching a certain level. A high fuel cell performance, 0.75 W cm-2, was achieved at 580 °C. © 2010 Elsevier B.V. All rights reserved. Source


Raza R.,KTH Royal Institute of Technology | Raza R.,COMSATS Institute of Information Technology | Abbas G.,COMSATS Institute of Information Technology | Abbas G.,Bahauddin Zakaria University | And 4 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2012

Nanocomposite based cathode materials compatible for low temperature solid oxide fuel cells (LTSOFCs) are being developed. In pursuit of compatible cathode, this research aims to synthesis and investigation nanocomposite La 0.3Sr 0.2Mn 0.1Zn 0.4 oxide-Sm 0.2Ce 0.8O1.9 (LSMZ-SDC) based system. The material was synthesized through wet chemical method and investigated for oxideceria composite based electrolyte LTSOFCs. Electrical property was studied by AC electrochemical impedance spectroscopy (EIS). The microstructure, thermal properties, and elemental analysis of the samples were characterized by TGA/DSC, XRD, SEM, respectively. The AC conductivity of cathode was obtained for 2.4 Scm ?1 at 550 °C in air. This cathode is compatible with ceria-based composite electrolytes and has improved the stability of the material in SOFC cathode environment. Copyright © 2012 American Scientific Publishers. All rights reserved. Source


Abbas G.,COMSATS Institute of Information Technology | Abbas G.,KTH Royal Institute of Technology | Raza R.,COMSATS Institute of Information Technology | Raza R.,KTH Royal Institute of Technology | And 5 more authors.
International Journal of Energy Research | Year: 2014

SUMMARY: Zn-based nanostructured Ba0.05Cu0.25Fe0.10Zn0.60O (BCFZ) oxide electrode material was synthesized by solid-state reaction for low-temperature solid oxide fuel cell. The cell was fabricated by sandwiching NK-CDC electrolyte between BCFZ electrodes by dry press technique, and its performance was assessed. The maximum power density of 741.87mW-cm-2 was achieved at 550°C. The crystal structure and morphology were characterized by X-ray diffractometer (XRD) and SEM. The particle size was calculated to be 25 nm applying Scherer's formula from XRD data. Electronic conductivities were measured with the four-probe DC method under hydrogen and air atmosphere. AC Electrochemical Impedance Spectroscopy of the BCFZ oxide electrode was also measured in hydrogen atmosphere at 450°C. © 2013 John Wiley & Sons, Ltd. Source


Abbas G.,Bahauddin Zakaria University | Abbas G.,COMSATS Institute of Information Technology | Abbas G.,GETT Fuel Cell AB | Chaudhry M.A.,Bahauddin Zakaria University | And 7 more authors.
Nanoscience and Nanotechnology Letters | Year: 2012

Composite electrodes of Cu 0.16Ni 0.27Zn 0.37Ce 0.16Gd 0.04 (CNZGC) oxides have been successfully synthesized by solid state reaction method as anode material for low temperature solid oxide fuel cell (LTSOFC). These electrodes are characterized by XRD followed by sintering at various time periods and temperatures. Particle size of optimized composition was calculated 40-85 nm and sintered at 800 °C for 4 hours. Electrical conductivity of 4.14 S/cm was obtained at a temperature of 550 °C by the 4-prob DC method. The activation energy was calculated 4×10-2 eV at 550 °C. Hydrogen was used as fuel and air as oxidant at anode and cathode sides respectively. I-V/I-P curves were obtained in the temperature range of 400-550 °C. The maximum power density was achieved for 570 mW/cm2 at 550 °C. Copyright © 2012 American Scientific Publishers. Source

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