Department of Physics
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Item Tuning the Ionic Conductivity of Electrolyte Material to Optimize/Enhance the Solid Oxide Fuel Cell Performance(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Nabgah Tariq; CIIT/SP22-RPH-008/LHR; Dr. Ghazanfar Abbas; LHR TP 8779The world is using up non-renewable energy sources quickly. Fossil fuel-based energy supplies may run out in a century and two decades. Fossil fuels have many harmful effect on human health and environment. Although fuel cell have received a lot of interest because there great efficiency, simplicity, low impact on the environment, cost effective and fuel adaptability. All fuel cell types, solid oxide fuel cells (SOFCs) is gaining more popularity. Ba-SDC, Sr-SDC, Ca-SDC & Ti-SDC was used as an electrolyte improve properties of solid oxide fuel cell. Due to this purpose electrolyte material was synthesized by co-precipitation method. Prepared material analyzed by various technique such as Raman, UV-Visible, Fourier transform infrared spectroscopy, Conductivity measurement & Open circuit voltage (OCV). Raman sample expose strong peak between 600cm-1 to 1200 cm-1, which may be predict the vibration mode and change in structure. It describes the kind of shifting that occur in prepared material. The presence of blue shift in material may be shows heavy atoms in material by which its bound length got shorter and the red shift predict bound length increase by increase by wavelength also it shows the active modes (F1g, A1g and Eg). By UV-visible, synthesized sample's band gap and absorbance are detected. FTIR provides information on the presence of functional groups in materials as well as the organic or inorganic behavior of manufactured materials. With the aid of temperature dependent EIS, the conductivity of materials may be computed. Ti-SDC shows maximum conductivity at 700°C and having value 0.090 S/cm. Using hydrogen as fuel improves the conductivity of materials by utilizing fuel cell performance at temperatures ranging from 500°C to 700°C.Item Tuning the Catalyst Materials in Anode to Improve the Electrochemical Properties of Low Temperature Solid Oxide Fuel Cell(LHR TP 7695, 2021) Omer Abbas; CIIT/SP20-RPH-047/LHR; Dr. Ghazanfar Abbas; LHR TP 7695In present study zinc-based anode materials with composition Ba0.10Cu0.20M0.10Zn0.60 oxide (where M represent Mn, Mo, and Ag) were synthesized via cost effective sol-gel technique. The effect of suggested M components was observed to understand the electronic conduction mechanism with the diffusion of the hydrogen ion. In this work, materials synthesized by sol-gel technique and their functionalities are investigated as an anodic function of solid oxide fuel cell (SOFC). Their investigations consist of various characterizations such as Fourier Transformation Infrared Spectroscopy (FTIR), Raman Spectroscopy, X-ray diffraction (XRD) and Electrochemical Impedance Spectroscopy. FTIR technique is employed to analyse the chemical composition and its bounding. The Ba0.1Cu0.2Ag0.1Zn0.6O show that the peaks at 667 cm-1 738 cm- 1, 1121 cm-1, 1331 cm-1, 1664 cm-1, and 3238 cm-1 belong to Zn-O vibrational energy bond, the vibrational bond of C-O (symmetric) of ZnO, Zn-O stretching bonds and O-H hydroxyl group, respectively. The Ba0.1Cu0.2Mo0.1Zn0.6O show that the peaks at 675 cm-1 762 and 1339 cm-1, 1042 cm-1, 1121 cm-1, and 3010 cm-1are associated with the O-H bond, C-O bond, and C-H group, respectively. The Ba0.1Cu0.2Mn0.1Zn0.6O show that the peaks at 667 cm-1 754 cm-1, 875 cm-1, 1323 cm-1, 1113 cm-1, and 3644 cm-1 belong to Mn-O stretching bond, Zn-O vibrational energy, Zn-O bond, Zn-N bound bond, and O-H hydroxyl group, respectively. Raman spectroscopy is used to detect vibrational, rotational, and other states in a molecular system, capable of probing the chemical composition of materials. The Ba0.1Cu0.2Ag0.1Zn0.6O Raman pattern that the peak at 431 cm-1 belong to E2 High-E2 LOW mode of Zn-O, at 135 cm-1 peak associate to E2 High mode of Cu-O, and at 577 cm-1 relate to Cu-O, at 1144.54 cm-1 and peaks 1071 cm-1 related to AgO, and 1144 cm-1 linked to multi-phonon scattering process. The The Ba0.1Cu0.2Mo0.1Zn0.6O Raman pattern that the peaks observed at 135 cm- 1, 325.76 cm-1 for Cu-O and MoO, 577.18 cm-1 belongs to Cu-O, Zn-O at 435.3 cm-1 and 792.4, 837.4,8.889 and 1149 cm-1 relate to Mo-O bond. While, at 1149 cm-1 peak associate to the glass substrate. The Ba0.1Cu0.2Mn0.1Zn0.6O Raman pattern that the peaks at 337 cm- 1, 432 cm-1 belong to Zn-O mode of E2 high-E2 low, and E2 high, respectively. A peak at 659 cm- 1 belongs to the Mn-O group. While, at 964 cm-1 peak associate to the glass substrate, but at 1164 cm-1 is C-H group. X-ray diffraction used to calculate the crystal phase, cell parameter, volume, and density of a material. The Ba0.1Cu0.2Ag0.1Zn0.6O XRD pattern describes that oxide materials have composite nature consist of three-phase structures, where the phase of Zn-oxide (hexagonal structure, JCPDF 01-079-2205) may be in-cooperated with the phase of BaAg6O4 (orthorhombic structure, JCPDF 01-71-0749) and Cu-oxide (monoclinic structure, JCPDF 00-048-1548). The average crystallites sizes were found to be 85.2 nm, 96 nm, and 63.67 nm, respectively. The XRD pattern of Ba0.1Cu0.2Mo0.1Zn0.6O describes that oxide materials have composite nature consist of three-phase structures, the Cu-oxide (monoclinic structure, JCPDF 00-048-1548), BaMoO4 phase (tetragonal structure, JCPDF 00-008-0455), and Zn-oxide (hexagonal structure, JCPDF 01-079- 2205). The average crystallites sizes were found to be 78.45 nm, 65.63 nm, and 85.46 nm, respectively. The XRD pattern of Ba0.1Cu0.2Mo0.1Zn0.6O revealed that oxide materials have a three-phase structure, Zn-oxide (hexagonal structure, JCPDF 01-079-2205) is maybe in-cooperated with the phase of BaMn8O16 (tetragonal, JCPDF 00-029-0188) and Cu-oxide (monoclinic structure, JCPDF 00-048-1548). The average crystallites sizes were found to be 71 nm, 64 nm, and 57.6 nm, respectively. The Electrochemical properties were investigated by AC Electrochemical Impedance Spectroscopy (EIS) technique by 4-probe method under air and hydrogen atmosphere. The materials show the increasing behavior, with enhancing the temperature, which describes the nature of semiconductors and performance work of SOFC is under processItem Fabrication and Characterization study of Micro Thin Film Electrolyte for the Solid Oxide Fuel Cell (SOFC)(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) RIZWAN ASGHAR; CIIT/SP20-RPH-033/LHR; Dr. Muhammad Ajmal Khan; LHR TP 7691In this study, Calcium Doped Ceria (CDC) thin film is prepared by the two steps, in the first step calcium doped ceria (CDC) powder is synthesized by co-precipitation method and in the second step, the slurry of calcium doped ceria (CDC) with ball milling and then thin film is casting with help of Tape casting technique. The fabricated thin films were sintered in the range of temperatures (150-750) ℃, in an air atmosphere. Crystal structure revealed that thin film has a cubic fluorite structure, and its average crystallite size is in the range of (53-42) nm. Raman analysis of the thin film was done in the temperature range of 350-750℃. These results showed that CDC thin films have high oxygen vacancies as sintering temperature rises. Which was depicting the high conductivity of the thin film. These results were also verified by the Conductivity measurements. The increase in FWHM of main peaks of Raman spectra, with an increase in temperature resulting in reduction of the crystallite size. Which was also confirmed by XRD results. FTIR results showed the formation of the Ce-O bonds, OH stretching, etc. Furthermore, FTIR spectra of the thin film at various temperatures indicated that OH stretching decreased as temperature increased, indicating that moisture in the sample reduced. Uv visible analysis was done at two different temperatures, 150 and 750℃. Band gap values decreased with increase in the temperatures. It was 3.22eV at 750oC and 3.3eV at 150℃. The conductivity measurements showed that conductivity of thin film was increasing as sintering temperature rises. which was confirmation of Raman results. Thin-film showed the highest conductivity 0.052 Scm-1 at 750℃, the activation energy and electrical band gap calculated from the Arrhenius plot are 0.25 eV and 0.5 eV for the sample sintered at 750oC, respectively. EIS spectra thin-film sintered at 750℃ and 150℃ showed semicircle, which confirms the ionic behavior of the CDC electrolyte thin film. The ohmic resistance also decreased with an increase in the sintering temperature. These results revealed that the thin film shows high ionic conductivity at intermediate temperatures. Which makes it useful for SOFC application.Item Synthesis of Bismuth Doped Lanthanum Cobalt Iron Oxide Material as Cathode for Application of Solid Oxide Fuel Cell(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) ZOBIA ARIF; CIIT/SP20-RPH-027/LHR; Dr. Muhammad Ajmal Khan; LHR TP 7714To reduce carbon dioxide emissions, which create global warming and climate change, the world is moving toward renewable energy sources. Solid oxide fuel cells are one of the most effective energy generation technologies due to their high energy conversion and low environmental impact. In this project, we are synthesized the bismuth doped lanthanum cobalt iron oxide cathode material. The proposed materials are bismuth doped lanthanum cobalt iron oxide (Bix (La0.5Co0.45 Fe0.05)1-x (BLCF)), where x=0.1, 0.2, 0.3 & 0.4 are prepared by sol gel technique. Different characteristics of cathode materials Bix (La0.5Co0.45Fe0.05)1-x are study in this project are X-ray diffraction (XRD), Raman spectroscopy, Fourier Transformation Infrared Spectroscopy (FTIR) and DC-conductivity by four probe methods. The Bi0.1 (La0.45Co0.405Fe0.045) XRD pattern shows that material has composite phase. The phase of Bismuth Iron oxide (average crystalline size 63.63 nm) has an orthorhombic structure (ICSD card No 96-900-8149), Bismuth Lanthanum Oxide (average crystalline size 50.65) has an orthorhombic crystal structure (ICSD card No 96-100-1472) and Lanthanum Cobalt Oxide (average crystalline size 26.42 nm) having orthorhombic crystal structure (ICSD card No 96-200-2266). In Bi0.2 (La0.4Co0.36Fe0.04) XRD pattern Lanthanum Bismuth Oxide (ICSD card No 96-901-5834) and Bismuth Cobalt Iron Oxide (ICSD card No 96-433-6779) having hexagonal structure with crystalline size 93.4 and 76.1 nm. The 3 rd sample Bi0.3 (La0.35Co0.315Fe0.035) XRD pattern shows Bismuth Cobalt Iron oxide (ICSD card No 96- 433-6780), Lanthanum Cobalt Oxide (ICSD card No 96-200-2266) and Bismuth Lanthanum Oxide (ICSD card No 96-100-1471) having monoclinic, orthorhombic, orthorhombic structure with crystalline size 67.7, 65.8 and 76.3 nm. The XRD pattern of Bi0.4 (La0.3Co0.27Fe0.03) shows that Bismuth Lanthanum Oxide (ICSD card No 96-100-1471), Bismuth Iron Oxide (ICSD card No 96-900-8149) and Cobalt Oxide (ICSD card No 96-900- 5888) have orthorhombic, orthorhombic and cubic with crystalline size 56.2, 61.3 and 91.8 respectively. Raman spectra of all samples [Bi (LCF)] show prominent bands at 128, 281, 320, 374, 486, 595, 621, 645 and 980 cm -1 related to La sit vibration, Fe-O vibration, O-B-O O, CoFeO, Co- O, Ag symmetry, stretching vibrations and Ag and Bg normal modes. FTIR spectra of all xi samples [Bi (LCF)] show the peaks at 1060, 1098, 1117, 1426 and 3500 to 3800 cm -1 having different modes and bond (stretching of C-C, Bi O-H, Co precipitation O= C = O stretching vibrations and vibrational peaks). We use DC four-probe methods to measure conductivity of material at different temperature (300-600) ℃. The sample Bi0.4 (La0.3Co0.27Fe0.03) shows the maximum conductivity (6.9 S/cm) at temperature 650 °C. We use EIS techniques to find the ORR of cathode material at (350 to 650 ℃) in air atmosphere. The sample Bi0.4 (La0.3Co0.27Fe0.03) shows the maximum ORR and good electronic behavior.Item The Mechanical Strength Effects in terms of Conductivity and Fuel Cell Performance for low Temperature Solid Oxide Fuel Cell (LTSOFC)(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2019) Muhammad Zubair; CIIT/FA17-RPH-066/LHR; Dr. Ghazanfar Abbas; LHR TP 5740Energy is one of the essential factors for human progress and is the bedrock of present-day improvement, however there is an extraordinary setback in the supply of energy assets everywhere throughout the world because of increment sought after of energy. There are two fundamental energy assets that are utilizing to satisfy our energy necessity. These are, Non-sustainable energy source assets are limited and environmentally poison then again sustainable energy source assets are unlimited and friendly for environment. The overarching energy crises on the planet must be handled by utilizing reasonable energy sources. Fuel cell is one of the sustainable energy source assets which could be the elective energy source with no natural issue. This theory gives a methodology how to grow new nanocomposite electrolyte and cathode materials for low temperature strong oxide energy component (LTSOFC) based on nanocomposite way to deal with lower the working temperature of SOFC. Nano composite electrolyte ‘samarium doped Ceria (SDC)’ has been synthesized for LTSOFC by using co-precipitation method with precipitating agent of (sodium carbonates). Li, Ni, Cu carbonates are mixed with zinc nitrate by using solid state reaction method for solid oxide fuel cell electrodes. The structure and morphology of the synthesized nanocomposite electrolyte and electrode was examined by X-Ray diffraction (XRD). The Fuel Cell Performance was tested at temperature (300-650 °C). The Ionic Conductivity of the sintered nanocomposite was measured by four probe DC method. XRD patterns of the samples reveal that synthesized materials are nanostructured. The SDC has single phase material of cubic structure while the LNCZ material has two phase material, first phase is zinc oxide (ZO) of hexagonal structure and second is nickel oxide (NiO) of cubic structure. The ionic conductivity of 0.13S/cm at 650°C for 𝐶𝑒0.8𝑆𝑚0.2 and 1.65 S/cm at 650°C for (𝐿𝑖0.18𝐶𝑢0.18𝑁𝑖0.32𝑍𝑛0.32) has been achieved. The fuel cell performance was checked at the temperature of 400 °C to 650 °C with three layers of cell in which smarium based nanocomposite material as an electrolyte. It gives excellent performance with maximum power density 525mW𝑐𝑚−2 at 650 °C temperature.Item Comparative Studies of Oxide, Protonic and Hybrid Ions Conduction for Low Temperature Solid Oxide Fuel Cell(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2019) Zohaib Ur Rehman; CIIT/FA17-RPH-008/LHR; Dr. Ghazanfar Abbas; LHR TP 5712In present study novel electrolyte materials for oxide, protonic and hybrid ions conductors LN-Ca0.1Sm0.1Ce0.8O3–δ-Y2O3, LN-Ba0.1Sr0.1Ce0.8O3–δ-Y2O3, and LN-Ba0.1Sm0.1Ce0.8O3–δ- Y2O3 were synthesized via cost effective co-precipitation technique. Effect of alkali carbonates considered to diffuse the hydrogen ion and enhances the ionic conduction. Electrochemical properties were investigated by fuel cell performance and DC 4-probe method under air and hydrogen atmosphere. Experimentally structure, morphology and IR behavior characterized by XRD, SEM and FTIR respectively. Average crystallite size was calculated in the range of 27 to 98 nm by X-ray diffraction. Particle size was observed in the range of 40 to 100nm. Maximum conductivity achieved 0.19 Scm-1 for LN-Ba0.1Sm0.1Ce0.8O3–δ-Y2O3 that is greater than comparatively conventional electrolyte. Maximum power density 752mWcm-2 with current density 2010 mAcm-2 at 1.06 V for hybrid ion conductor taken into account by providing hydrogen fuel. Appearance of water during fuel cell testing on both ends of cell (anode/cathode) verify that dual ion conducts through this electrolyte material. Degradation and stability also found through durability.Item Incorporation of Copper Oxide in La0.8Sr0.2Ga0.8Mg0.2O3 (LSGM) Electrolyte Material for Solid Oxide Fuel Cell(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Sadia Haider; CIIT/FA23-RPH-034/LHR; Dr. Rizwan Raza; LHR TP 9860Solid oxide fuel cells (SOFCs) are efficient and low-emission energy conversion devices that operate by directly converting chemical energy into electrical energy. Despite their advantages, conventional SOFCs require high operating temperatures (~1000 °C), which lead to increased material degradation, cost, and limited lifespan. To address these challenges, research has focused on developing electrolyte materials that perform effectively at intermediate temperatures (500–800 °C) while maintaining high ionic conductivity and chemical stability. Lanthanum gallate-based perovskites, particularly La₀.₈Sr₀.₂Ga₀.₈Mg₀.₂O₃₋δ (LSGM), are among the most promising candidates due to their excellent oxide-ion conductivity and compatibility with SOFC components. In this study, copper oxide (CuO) is introduced as a dopant at the gallium site within the LSGM structure to enhance ionic conductivity while preserving structural and chemical stability under reducing conditions. The copper-doped LSGM electrolyte materials will be synthesized using the coprecipitation method. The dried precursors will be sintered at 800 °C, and the resulting samples will be characterized using Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and UV-Visible spectroscopy to analyze crystal structure, functional groups, phase composition, and optical properties. The synthesized samples will be pelletized, and their ionic conductivity will be measured through electrochemical impedance spectroscopy (EIS), with performance testing carried out under hydrogen fuel conditions. The study also investigates the effect of sintering aids on densification and grain boundary resistance. This research aims to develop a structurally optimized and thermally stable Cu-doped LSGM electrolyte, contributing to the advancement of high- performance SOFCs that operate efficiently at intermediate temperatures.