Browsing by Author "Dr. Ghazanfar Abbas"

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A Bismuth and Gallium Co-doped Cathode Materials for Intermediate Temperature Solid Oxide Fuel Cell
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) GHULAM MUSTAFA; CIIT/FA19-RPH-003/LHR; Dr. Ghazanfar Abbas; LHR TP 7262
To avoid carbon dioxide emissions, which cause global warming and climate change, the trend is turning toward renewable energy sources. Because of their high energy conversion and low/zero emissions, solid oxide fuel cells (SOFCs) are one of the finest solutions for energy production. SOFC is a fantastic choice for using biogas as a clean and high-energy conversion. There are still a few issues to work out, particularly for SOFCs with biogas fuel that operate at intermediate to lower temperatures. The perovskite structure plays a vital role in meeting the materials requirements for SOFCs.As a result, strontium-based perovskite structured cathode materials were created in this study. Strontium cobalt bismuth gallium oxide (SrCo1-x-yBixGayO3–δ (SCBG)) is the suggested material, with x=0, 0.1,0.2 and y=0, 0.1,0.2. The sol gel technique was used to prepare allof the samples. This study looks at the functions of cathode materials (SrCo1x- yBixGayO3–δ (SCBG)). Raman spectra of LSCF cathodes reveal prominent bands at peak positions, 130,420,515, 632, and 990 cm-1 wavelengths, corresponding to bonds characteristic vibrations and, optical phonon mode. Because it generates more oxygen ion vacancies, SCBG is a great cathode material, enhancing the oxygen reduction reaction (ORR) at the cathodic sites. XRD pattern of SCB10 and SCG10 is observed in such a way that crystalline structure was 38.65 and 38.13 nm respectively, that was confirmed by using SEM that concluded grain size 30-60 nm. The structure of proposed materials are rehmbohedral and hexagonal for SCB10 and SCG10 respectively. Sem confirmed that our samples are porous and has spheriacal and cylendrical particle shape that allows the maximum space to oxygen vaccencies. The low ohmic resistance metre KD2531 is use to assess the DC conductivity of SCBG cathode samples. At 600 °C, the sample SCBG20 from citric extracts has a maximum conductivity of 28.125 Scm-1 and ASR 0.0565 Ωcm2, via citrus extracts at 600 °C.
Alkaline Metal Coated Nanostructured Doped Ceria Electrolyte For Low Temperature SOFCs
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Bushra Mumtaz; CIIT/FA22-RPH-017/LHR; Dr. Ghazanfar Abbas; LHR TP 9431
In this study, electrolyte was fabricated for solid oxide fuel cells. Alkaline (Ba, Ca, Sr) coated samarium doped ceria and gadolinium doped ceria electrolyte for solid oxide fuel cell was prepared successfully. All of these samples were prepared by co- precipitation method. These materials give better results and produce more oxygen ions vacancies which enhance the oxidation reduction reaction. The synthesized material characterized by using Raman Spectroscopy, Uv-Vis spectroscopy, X-ray diffraction and Electrochemical Impedance Spectroscopy. Raman spectra show vibration modes and the structure of materials particles. Raman analysis of samples was done from 700- 900 °C. These results showed the strong peak of cerium oxide in range of 450 to 470nm and the weak intense peak representing oxygen ion vacancies. It tells about which type of shifting occurring in prepared material. In all prepared materials, there is blue shifting and wavelength is decreasing which show that particles size is decreasing. In UV-Vis spectroscopy result demonstrated the band gap values which ranges from 1eV to 2.5eV. With the help of XRD compositions and structure was confirmed, which is found to be cubic. EIS tells about the ionic and electronic behavior of materials. EIS tells about ohmic resistance, polarization resistance and total resistance of the material. EIS tells about charge transfer and mass transfer in material. The conductivity of materials can be calculated with the help of EIS, which is found to be 0.005Scm-1 at 550°C.
Approaches Towards Boosting the Ionic Conductivity of Electrolyte Materials for Low-Temperature Solid Oxide Fuel Cells
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) SARFRAZ; CIIT/SP20-RPH-051/LHR; Dr. Ghazanfar Abbas; LHR TP 7698
BaZr1−X GaX O3−δ (where x=0.1, 0.3 and 0.5) electrolyte materials for solid oxide fuel cell (SOFC) are synthesized in this research project. Cost effective co-precipitation, solid state reaction, and sol-gel methods are used to synthesize the electrolyte materials for SOFC. All the materials are sintered at low temperature (800℃) and low sintering effect also is discussed. Crystal structure, element composition and functional group are studied by XRD, FTIR and RAMAN spectroscopy. XRD confirms the peroveskite based cubic structure with Pm3m space group. The crystallite sizes are calculated in the range of 29.67 - 15.37 nm. FTIR and Raman analysis confirm the functional groups, stretching and bending modes. The maximum conductivity of BZG was recorded to be 0.065 S/cm at 750 ℃ (when x = 0.1 via co- precipitation).
Boosting the Electrochemical Activity of BSMO Cathode by Compositing (Sm0.20Ce0.50Bi0.30)2O3+δ for Low Temperature Solid Oxide Fuel Cell
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Muhammad Amir; CIIT/SP24-RPH-006/LHR; Dr. Ghazanfar Abbas; LHR TP 10120
Among energy conversion devices solid oxide fuel cells (SOFCs)are promising candidates due to their fuel flexibility and highly efficient; though, but their commercial application is limited due the high temperature. In this research work barium and strontium based low temperature solid oxide fuel cells (LT-SOFCs) were fabricated and characterized as cathode material for LT-SOFCs. Solid state method was adopted to synthesize barium strontium manganese oxide (Ba₀.₇₅Sr₀.₂₅MnO)₃−δ (BSMO) and (Sm₀.₂₀Ce₀.₅₀Bi₀.₃₀)₂O₃+δ (SCBO) was synthesized via the reverse co-precipitation route. The crystallographic crystal of the synthesized material was analyzed by employing XRD and all the samples shows highly crystalline structure. The characteristic vibrational modes of Sm-O, Ba–O, Ce-O, and Mn–O were confirmed from Raman spectroscopy. The BSMO, SCBO and BSMO/SCBO composite were fabricated via solid state mixing and electrochemical impedance spectroscopy (EIS) spectroscopy measurements were recorded with in the temperature range 400oC-700oC and enhanced electrochemical characteristics of the SCBO material was observed. It was observed that the BSMO/SCBO composite exhibited lower polarization resistance compared to pristine BSMO and SCBO within the temperature range of 550°C –650 °C, that results the improved ionic–electronic conductivity balance and enhanced charge transfer. DC conductivity measurements showed the semiconducting behavior of BSMO material and reduce and stable conductivity for SCBO, and intermediate conductivity value of conductivity for the composite material. All samples show the high open circuit voltage value (1.05 V) at 650 °C. The Fourier transfer Infrared (FTIR) spectroscopy was employed to study the functional groups. The results shows that the synthesized novel BSMO, SCBO and their composites can be the efficient materials for the future low temperature SOFCs applications.
Catalytic study of Cobalt-Free Cathode Materials for Ceramic Fuel Cells
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Nadia Sana Saboor; CIIT/SP23-RPH-008/LHR; Dr. Ghazanfar Abbas; LHR TP 9629
The great efficiency and fuel adaptability of ceramic fuel cells (CFCs) make them a promising route towards sustainable energy conversion. However, cobalt, a vital component of conventional cathodes, is expensive and scarce, which prevents the widespread use of CFCs. The catalytic investigation of cobaltfree cathode materials, namely SrFeMoW, for enhanced CFC performance is the main topic of this research. Our main objective is to improve the performance and temperature tolerance of the SOFC. We wish to address a few problems that cause it to operate slowly and less effectively. The present study will employ specialized manufacturing processes, including screen printing and tape casting, to regulate the component thickness of the SOFC. This will enhance the SOFC's performance and help it conduct electricity more effectively. I will make a Cobalt-free composite cathode which is cost-effective and which will operate at lower temperatures. This cobalt-free cathode will be prepared with the help of the sol-gel method. Using a variety of experimental methods, such as X-ray diffraction (XRD), Raman spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), UV-Vis spectroscopy, electrochemical impedance spectroscopy (EIS), and fuel cell testing, the study examines the structural, electrochemical, and catalytic characteristics of SrFeMoW. These methods shed light on the material's electrical characteristics, phase purity, chemical bonding, crystal structure, and electrochemical behavior. The impact of several doping techniques and synthesis parameters (such as temperature and environment) on the material's microstructure, oxygen reduction reaction (ORR) activity, and overall cell performance is methodically assessed. Using a multi-technique characterization approach, gain a thorough grasp of the structure-property interactions in SrFeMoW cathodes. Improve SrFeMoW stability and catalytic activity by optimizing its production and processing. Examine how doping with different elements (such as transition metals and rare-earth metals) affects the ORR kinetics and long-term durability. Compare the performance of SrFeMoW-based cathodes with that of traditional cobalt-based cathodes in single cells.
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 5712
In 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.
Development of La0.63Ga0.37Nb0.74Fe0.26O3-δ Electrodes for Solid Oxide Fuel Cells Via Various Synthesis Routes
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Hamza Gulzar; CIIT/FA23-RPH-018/LHR; LHR TP 9849; Dr. Ghazanfar Abbas
In this study, La₀.₆₃Ga₀.₃₇Nb₀.₇₄Fe₀.₂₆O₃-δ electrodes developed through four different methods for use in solid oxide fuel cells operating at intermediate temperatures are systematically investigated in this study. Coprecipitation, sol gel, solid state, and hydrothermal synthesis were the techniques that were compared. The coprecipitation approach was shown to be the best synthesis route after thorough analysis, exhibiting superior structural and electrochemical features. In coprecipitated samples, Raman spectroscopy showed prominent Ga–O symmetric stretching at 532 cm⁻¹, La–O stretch at 400 cm⁻¹, and Fe–O modes at 656, 713 cm⁻¹. Nb–O vibration was observed at 882 cm⁻¹, with distinct vibrational modes suggesting increased crystallinity and oxygen vacancy generation. The material's phase features were validated by XRD analysis showing broadened peaks corresponding to nanocrystalline structure with 12.9 nm crystallite size, and reference phases confirmed by JCPDS 01-084-1020 (FeNbO₄) and 03-065-0945 (GaLaO₃-type). An ideal band gap of 1.44 eV was found by UV–Vis spectroscopy, indicating advantageous electronic characteristics. Electrochemical impedance spectroscopy revealed the lowest polarization resistance values of 4.1 Ω at 600°C and 3.1 Ω at 650°C, among all samples. Fuel cell testing showed that coprecipitated samples excelled sol gel at 0.890 V, solid state at 0.870 V, and hydrothermal at 0.843 V, reaching the highest open circuit voltage of 0.960 V at 650°C. The desirable structure, phase purity, and defect composition of coprecipitated electrodes are responsible for their exceptional performance. Offering considerable potential for developing sustainable energy conversion technologies, these results solidify coprecipitation as the preferred synthesis technique for high performance intermediate temperature solid oxide fuel cell electrodes. The goal of future studies should be to scale manufacturing while preserving these beneficial characteristics.
Electrochemical Investigation of Lanthanide Incorporated Sr0.5R0.3Fe0.2CoO3-δ Cathode Materials for Solid Oxide Fuel Cell
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Kainat Zafar; CIIT/FA23-RPH-022/LHR; Dr. Ghazanfar Abbas; LHR TP 9853
The fossil fuel-based energy resources are widely providing predominant amount of worldwide energy such as coal, oil, and gas. Unfortunately, due to high consumption rate and the current generation demands, these limited assets are being depleted rapidly. Therefore, it is urgent need to find out some alternate energy resources which should be renewable. One kind of fuel cell that is well-known for its great efficiency and capacity to function at high temperatures usually between 600°C and 1000°C is the solid oxide fuel cell (SOFC). To carry oxygen ions from the cathode to the anode, where the fuel is oxidized and energy is produced, they use a solid oxide or ceramic electrolyte. The cathode material has a major impact on SOFC performance; it needs to have strong catalytic activity, chemical stability, and electronic conductivity. In this regard, lanthanide-incorporated Sr0.5R0.3Fe0.2CoO3-δ (where R = Ce, Gd, and Sm) cathode materials are being studied to boost SOFC performance. Higher efficiency and durability can result from the addition of lanthanides, which can also enhance the catalytic and electrical conductivity. By improving SOFC performance, this novel strategy hopes to increase their viability for clean energy applications and promote the development of sustainable energy technology. The goal of this research work is to improve the efficiency of SOFCs by studying lanthanide-incorporated Sr0.5R0.3Fe0.2CoO3-δ cathode materials. Sr0.5R0.3Fe0.2CoO3-δ materials will be synthesized by solid state reaction and characterized by XRD, SEM, RAMAN, UV- Vis, FTIR and EIS. Electrical conductivities and fuel cell performance will be measured under hydrogen atmosphere. By optimizing the cathode's properties, this novel strategy seeks to promote clean energy solutions by increasing efficiency, extending operational lifespans, and expanding the applications of SOFC technology.
Electrochemical study of Graphene/ Graphene Oxide/ Reduced Graphene Oxide in Fuel Cell
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2018) MUHAMMAD EHSAN; CIIT/FA15-RPH-034/LHR; Dr. Ghazanfar Abbas; LHR TP 6413
Graphene is of major importance in a very wide range of applications. Different works are under progress to make the products better in durability, performance and in other properties using graphene. In this work, the major objective was focused to use the graphene/graphene oxide/reduced graphene oxide into Solid Oxide Fuel Cell (SOFC) to reduce its operating/working temperatures with better performance. As SOFC operates at high temperature that is one of the major problems, so by using graphene/graphene oxide/reduced graphene oxide the performance and durability of SOFC will be under consideration at a temperature of < 600 °C. It could provide good performance in asymmetrical solid oxide fuel cell because it can be a good potential to be an alternative cathode material for LT-SOFCs. For the confirmation of results different characterization tests are performed including XRD, SEM, DC conductivity and Fuel cell performance. In this work the newly developed SOFC materials are analysed to check the performance/efficiency and find the applications in new energy devices. In this project, I prepared 12 nanocomposite anode materials for LT-SOFC. All samples were successfully synthesized by simple and cost effective methods (Sol-gel method and Solid State). The XRD results show that the synthesized materials are in nano scale. The structure of the all samples was Perovskite. The average crystalline size of all prepared sample lies in the range of 22-300 nm. The sample LNCZ + 30% GO shows the maximum electrochemical performance as compared to other compositions of graphene Oxide and graphene. The electrochemical performance of LNCZ + 30% GO was measured with OCV of 0.155V, current density 450 mAcm-2, power density 105 mW/cm-2 at 4000C with the hydrogen fuel. It shows better results as compared to graphene because it has dual phase composite structure and since its oxide material so GO treat batter with LNCZ-Oxide rather the graphene. The nanocomposite structures help to enhance the conductivity and performance of the cell at low temperature. So this nanocomposite material which have perovskite structure can be considered as better anode materials for LTSOFCs.
Hybrid Ion Conductors Membrane for CO2 Separation
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2018) TAUQEER AHMAD; SP16-RPH-028; LHR TP 5246; Dr. Ghazanfar Abbas
CO2 is emitted in a very large amount per year by the different fossil fuel industries for the generation of energy which is the major origin of GHG in the climate. CO2 emission is a major worldwide problem of today. Different works have been done for the reduction of CO2 emission gas and numerous types of works are under process. In our project the major focus is to separate the CO2 by hybrid ion conductors membrane of solid oxide fuel cell. For this purpose, GDC/Li2CO3-Na2CO3 (LN-GDC) nanocomposite electrolyte material was synthesized with molar ratio 1:3 by co precipitation method. The sample was dried in oven and filtered by suction pump followed by sintering at temperature 700oC in a digital furnace. The prepared sample LN-GDC was further characterized by different techniques; XRD, SEM, FTIR including conductivity measurements by four probes DC method. The XRD and SEM results confirm that the synthesized material lies in nano scale, homogeneous and dense in nature. However, the major study was focused to analyze the CO2 separation from this membrane so the sample was further reformed in polymer membrane and chloroform was used as a solvent for the preparation of dense hybrid membrane. This modified prepared hybrid membrane is used for the separation of CO2 gas
Insight into Metal Oxides FexMn1-xO-SDC as an Oxygen Carrier for Fuels Cells and Chemical Looping
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2023) ASMAA SAEED; CIIT/FA21-RPH-001/LHR; Dr. Ghazanfar Abbas; LHR TP 8587
Due to the rise in energy demand, the globe is moving closer and closer to a serious power crisis [1]. Due to its expanding population and weak long-term planning for its energy-based infrastructure, Pakistan is currently experiencing its biggest energy crisis [2,3]. The installation of thermal power plants has largely served as the focus for short-term solutions [2]. Fossil fuels are imported into Pakistan for usage in thermal power plants, which use them to generate electricity. Energy generated from imported fuel is an incredibly costly solution for a growing country like Pakistan [4]. Nuclear power facilities have also been built; however, they have limited capacity [5]. The potential environmental risk posed by these thermal power facilities is also disregarded. Pakistan's primary energy production sources are oil (35.20%), hydel (29.90%), natural gas (29.00%), nuclear energy (5.70%), and imported energy. The average annual energy consumption in Pakistan is 17,000 MW, while there is now a 400–5000 MW shortage. It is expected that within the next ten years the demand for energy might increase by 4-5%, or around 1500 MW [6]. It is not environmentally good to use fossil fuels, especially carbon, to generate electricity. On the other hand, environmentally friendly renewable energy sources provide a more affordable solution as shown in fig. 1.1 [7, 8]. With the utilization of renewable energy sources, Pakistan must overcome problems in its energy planning [9]. Therefore, in addition to concentrating on these standard energy sources, fuel cell (FC) technology should be used to investigate non-traditional energy sources such as solar, hydrogen, geothermal, wind, tidal power, and biomass [10, 11]. No other energy generating method can compare to the advantages provided by FC technology [12].
Investigation of Catalytic Effect on Anode Material at Low Temperature Solid Oxide Fuel Cell
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) Munazza Mariyam; FA19-RPH-041; Dr. Ghazanfar Abbas; LHR TP 7239
The world's largest single drain is the energy problem. To avoid carbon dioxide emissions, which cause global warming and climate change, the world is moving toward renewable energy sources. Because of its great efficiency and minimal emissions, solid oxide fuel cells (SOFCs) are one of the best solutions for energy production. solid oxide fuel cell (SOFC) is the best option Because of the fuel flexibility and cost-effective anode materials features. The structural and electrochemical properties of anode materials with configuration of X0.1Zn0.45Ti0.45 oxide (where X = Ni, Cu, Fe,) have been examined in this current investigation. The proposed anode materials X0.1Zn0.45Ti0.45 oxide have been unify through sol-gel technique. The doping impact of Cu, Ni, and Fe on TiZn oxides were examine in respect of electronic conduction and power density in hydrogen environment at similarly low temperature in the range of 600°C. Four-probe DC conductivity method was utilized to quantify the conductivity of the anode materials and most extreme electrical conductivity. The four-probe method is used to determine conductivity. Using iron as a catalyst at temperatures of 600°C and 550°C, maximum conductivity of Cu0.1Zn0.45Ti0.45 oxide was found to be 12.56 S/cm and 8.695 S/cm. The band gap and absorption spectra were discover by ultra-violet visible (UV–Visible). The purity of nanoparticles is measured by the FTIR spectrum, which provides information about an infrared spectrum of absorption or emission. They give the bonding of molecular structure and chemical composition of the material. Xrd is use to study crystallographic structure of anode material. Crystalline size was found by schere’s equation. The level of structural flaws and the crystalline nature of the material were confirmed using Raman spectroscopy. The findings suggest that the developed (X=Ni,Cu,Fe) is a suitable catalyst of anode material for SOFCs.
Investigation of Catalytic Effect on Anode Material at Low Temperature Solid Oxide Fuel Cell
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) Munazza Mariyam; FA19-RPH-041; Dr. Ghazanfar Abbas; LHR TP 7239
The world's largest single drain is the energy problem. To avoid carbon dioxide emissions, which cause global warming and climate change, the world is moving toward renewable energy sources. Because of its great efficiency and minimal emissions, solid oxide fuel cells (SOFCs) are one of the best solutions for energy production. solid oxide fuel cell (SOFC) is the best option Because of the fuel flexibility and cost-effective anode materials features. The structural and electrochemical properties of anode materials with configuration of X0.1Zn0.45Ti0.45 oxide (where X = Ni, Cu, Fe,) have been examined in this current investigation. The proposed anode materials X0.1Zn0.45Ti0.45 oxide have been unify through sol-gel technique. The doping impact of Cu, Ni, and Fe on TiZn oxides were examine in respect of electronic conduction and power density in hydrogen environment at similarly low temperature in the range of 600°C. Four-probe DC conductivity method was utilized to quantify the conductivity of the anode materials and most extreme electrical conductivity. The four-probe method is used to determine conductivity. Using iron as a catalyst at temperatures of 600°C and 550°C, maximum conductivity of Cu0.1Zn0.45Ti0.45 oxide was found to be 12.56 S/cm and 8.695 S/cm. The band gap and absorption spectra were discover by ultra-violet visible (UV–Visible). The purity of nanoparticles is measured by the FTIR spectrum, which provides information about an infrared spectrum of absorption or emission. They give the bonding of molecular structure and chemical composition of the material. Xrd is use to study crystallographic structure of anode material. Crystalline size was found by schere’s equation. The level of structural flaws and the crystalline nature of the material were confirmed using Raman spectroscopy. The findings suggest that the developed (X=Ni,Cu,Fe) is a suitable catalyst of anode material for SOFCs.
Investigation of Divalent/Trivalent Metal Doping into SrFeO3 as a Cathode Material for Low Temperature SOFC
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Tariq Aslam; CIIT/SP23-RPH-011/LHR; Dr. Ghazanfar Abbas; LHR TP 9632
In this research, I have prepared cathode for low temperatures solid oxide fuel cells. Divalent (Ba, Mg) and Trivalent (Co, Al) were mixed in strontium ferrite oxide materials. Mixture of these samples were dried at 200℃ for 150 minutes in oven for its dehydration. Then, samples were passed through sintering process at 750℃ for 4 hours. Due to sintering at high temperature, our samples become dense, its many properties were changed at large temperature like, increase its mechanical strength of Nano materials, and boost up its bond strength and also material become homogeneous and stable. Fabricated material were characterized by UV- Visible spectroscopy, FTIR (Fourier transform infrared), and Raman Analysis. FTIR technique was set peaks at transmission of light with wavelength 400cm-1 and 4000 cm-1. FTIR peak at 1017 cm-1 indicate Fe–Ba–O bonds, carbonate groups and hydroxyl groups present at peak1453 cm-1 and 1642 cm-1 respectively, while 2834 to 2980 cm-1 peaks were denoted the CH2 and CH3 acetate formation. UV-visible is analytical technique which was proceed the data about sample composition, structural properties of the nano particles when light was transmitted in the materials at diverse wavelength. By Tuac plot of UV-visible we have calculated the band energy gap value Ba metal in SrFeO3 materials was measured 2.80eV, Eg of Al was 2.66 Ev. These energy values are required to excite the electrons form VB to CB to make the material conductive. Raman spectra illustrate the orthorhombic and FeO₆ octahedral structure at peaks ranges 123 to 664 cm⁻¹, tells about vibrational modes and presence of of oxygen vacancies, this show that more oxidation reduction reaction phenomena occur.
Investigation of Ionic Behavior of Boron Doped Ceria Oxide Ion Conductors using Electrochemical Techniques
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) Muhammad Nadeem; CIIT/SP20-RPH-022/LHR; Dr. Ghazanfar Abbas; LHR TP 7965
In this study, Boron Doped Ceria (BDC) ionic conductor is prepared by co-precipitation method. Three different samples with different concentrations of boric acid and cerium nitrate were synthesized with ratio B0.3Ce0.70, B0.20Ce0.80 and B0.10Ce0.90 named as BDC-1, BDC-2 and BDC-3 respectively. Sodium carbonate was used as precipitating agent in quantity 20% of total sample. Then fabricated electrolyte was sintered at the temperature 700 ℃ in the furnace. Raman analysis of the electrolyte was conducted to evaluate the vibrational and rotational modes of material. The intense peak showed the vibrational mode of cerium oxide and lower peak showed an oxygen vacancy over some range of 550-650 cm -1 . These results showed that BDC electrolyte have high oxygen vacancies with the increase in sintering temperature. FTIR results showed the formation of the Ce- O bonds, OH stretching, metal-oxide bonds and some residual material peaks. Furthermore, FTIR spectra of the ionic conductor revealed OH stretching indicating that moisture is present in the sample. The conductivity measurements showed that conductivity of BDC-2 was electrolyte 0.086 Scm -1 at 750 ℃. These results revealed that the BDC electrolyte shows high ionic conductivity at intermediate temperatures that makes it useful for SOFC application. Fuel cell performance for BDC electrolyte materials was analyzed by using BCFZ anode and LSCZ cathode and a plot of voltage was drawn. BDC-2 having medium amount of doped Boron achieved high OCV as compared to BDC-1 and BDC-3. It was observed that cerium is best conductor so, its conductive behavior elevates the OCV as compared to Gd and Sm.
Investigation of the Electrochemical Effect of Rare Earth Materials on Zinc based Anode for SOFC
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) ATIF HAYAT; CIIT/FA20-RPH-043/LHR; Dr. Ghazanfar Abbas; LHR TP 7999
Current scenario of the energy requirements motivates to researchers to explore the renewable energy resources. This also will be helpful to control the climate environmental issues to save the future. Fuel cells have aroused a lot of interest in this activity because of their high conversion efficiency when compared to traditional energy conversion approaches. Because of its low hazardous emissions, pollution, fuel adaptability, and cost-effective components, SOFCs are importance source for energy conversion technologies. Some issues are still need to be addressed, as conventional SOFC works at high temperature but the fact is that the SOFC activity reduces at low temperatures due to interfacial polarization blockages and the oxygen reduction process. In this context, in the present study zinc- based anode materials with composition Ce0.2(Zn0.5 Ni0.5)0.8, Sm0.2(Zn0.5 Ni0.5)0.8, Gd0.2(Zn0.5 Ni0.5)0.8 were synthesized via cost effective sol-gel technique. The effect of rare-earth materials has been investigated in terms of electrochemical properties. Their investigations consist of various characterizations such as Fourier Transformation Infrared Spectroscopy (FTIR), Raman Spectroscopy, UV-Vis, EIS, and fuel cell performance. FTIR is employed to analyse the chemical composition and its bounding. The FTIR spectrum the band at 1082 cm-1 can be attributed to the O- Ce-O stretching mode of vibration. The FTIR spectrum of zinc oxide nanoparticles absorbs at 648.50 cm−1. The absorption bands in the range of 743 cm−1 correspond to Ni-O stretching vibration mode. The large broad band at 3415cm-1 is ascribe to the O-H stretching vibration in OH groups. Raman spectroscopy is used to detect vibrational, rotational, and other states in a molecular system, capable of probing the chemical composition of materials. The Ce0.2(Zn0.5 Ni0.5)0.8 Raman pattern that the peak at 450-460 cm-1 attributed to Raman-active F2g mode of fluorite-structured CeO2. The Electrochemical properties were investigated by AC Electrochemical Impedance Spectroscopy (EIS) technique by 4-probe method under hydrogen atmosphere. The materials show the increasing behavior of conductivity with increasing the operating temperature. UV-visible characterization technique held to examine the optical properties of the sample and used to get the absorbance and reflectance spectra under the selected UV range of 190-800 nm. The fuel cell performance was carried out by making three –layers cell and maximum OCV was obtained 0.53V of Ce(NiZn) material.
Nanocomposites Anode Materials for Fuel Flexible Low Temperature Solid Oxide Fuel Cell
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2019) Muhammad Shakeel; FA17-RPH-061; Dr. Ghazanfar Abbas; LHR TP 5735
Broad efforts have been made to create multi-fuel-based low temperature solid oxide fuel cell that will directly utilize hydrocarbons to produce electric power. It is very difficult to work because of the C-H bond activation and its immensely slow oxidation reduction in the low temperature range from 300 to 600 °C. The structural and electrochemical properties of prepared anode materials Ba0.15Zn0.60Mn0.15-Ag0.10, Ba0.15Zn0.60Mn0.15 Cu0.10,Ba0.15Zn0.60Mn0.15-Fe0.10, have been investigated within the sight of hydrogen, natural gas and ethanol at a low temperature of 650 0C. Through sol gel process prepared anode materials are synthesized. The average crystallite size has been found in the range of 19-90nm by XRD. Conductivity is measured by four probe method. Maximum conductivity of 4.8 S/cm, 4.3 S/cm and 4.4 S/cm have been found by using silver, copper, and iron as a catalyst at a temperature of 600 °C, 550 °C and 580 °C respectively. The impact of prepared nanocomposite materials on the performance of solid oxide fuel cell is investigated. The power density of the cell at different fuels has been checked and measurements demonstrate it varies from 100 to 500 mW/cm2 at 650 0C among different fuels at the anode side. The present examination reveals that proposed anodes are promising multi-fuel material for low-temperature solid oxide fuel cell, and it doesn't have to change hydrocarbon fills to completely use the benefit of these cells.
Structural and Electrical Investigation of Co-Doped Ceria based Electrolytes for Fuel Cells
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) ZONAIRA AMEEN; CIIT/FA19-RPH-051/LHR; Dr. Ghazanfar Abbas; LHR TP 7237
In the fuel cell family, the most competent device for converting energy is the solid oxide fuel cell (SOFC) and has gained high considerable attention. The efficiency of SOFC highly depends on electrolyte materials that can work well at low temperatures. Ionic conductivity is good in a co-doped ceria-based electrolyte material. The most promising electrolyte materials for intermediate temperature solid oxide fuel cells (IT-SOFCs) have been ceria and doped ceria because it shows good ionic conductivity at 600-800 ºC which is still very high and a barrier towards commercialization. Therefore, in this project, the co-doped ceria electrolyte materials (GBDC, CBDC and SBDC) were developed using sol-gel and co-precipitation method. The functionalities of electrolyte materials are investigated in this research. Prominent bands at peak positions 360, 461, 482, 600, 602, 1059 and 1080 cm−1 wavelengths are observed through Raman spectra of co-doped ceria electrolytes, analogous to GdO F2g mode, the first order F2g active mode of CeO2's cubic fluorite structure, structure of CeO2 that shows symmetric stretching modes of O ions around Ce ions, indication of Ca-O, and Ba-O. Ceria based materials behaves as an excellent electrolyte material. The vibratory characteristics are studied through FTIR spectroscopy; different peaks are obtained that indicates different vibrational modes. The direct band gap of the synthesized electrolyte materials were calculated by Tauc plot and obtained 2.5 and 1.5 eV of Gd0.1Ba0.1Ce0.8 .and Ca0.1Ba0.1Ce0.8 respectively. The structural properties are studied with the help of XRD and obtained a cubic fluorite structure of SBDC electrolyte material. DC Conductivity measurements of samples are evaluated by four point probe method. The sample CBDC has maximum ionic conductivity values of 0.82 Scm-1 at 400 ˚C temperature. The results indicate that developed ceria based electrolytes materials are good for SOFC.
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 5740
Energy 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.
To investigate the Effect of Alkaline Earth Metals on Electrochemical Activities of Lanthanum Cobalt Zinc Oxide Cathode Materials
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) AQIB RAFIQUE NOORI; CIIT/SP20-RPH-024/LHR; Dr. Ghazanfar Abbas; LHR TP 7966
In the modern age of science and technology every system of manual work is transferring to machines and to run these machines energy is required, so the need of time is motivating researchers to enhance their activities in the scope of renewable energy production devices which will be able to produce more energy at very low cost. In this regard fuel cell got higher attraction of investigation due to its higher efficiency, environmentally friendly nature, and low cost. Solid oxide fuel cell (SOFC) is an extremely encouraging class of fuel cells. SOFC consists of electrolyte sandwiched between anode and cathode. In this research work, lanthanam-based cobalt Zinc oxide cathode materials are prepared by sol-gel route alongwith the characterizions for the cathode functioning of solid oxide fuel cell (SOFC). FTIR technique is employed to analyse the chemical composition and its bounding. In BaLaCoZn peaks are found at 853 cm -1 ,859 cm -1 and 1426 cm -1 which are corresponding to C-O, La-O and Co-O respectively. In CaLaCoZn peaks are found at 703 cm -1 , 988 cm -1 , 1433 cm -1 which are attributed to Zn-O, C-O,Co-O, respectively. In SrLaCoZn peaks are observed at 856 cm -1 , 950 and 1441 cm -1 which belong to Sr-O, Zn-O respectively. For Sr1Co0.8La0.2 (SCL) peaks are found at 157 cm -1 , 525 cm -1 , 957 cm -1 and 1363 cm -1 . The analysis of existence of each and every C-H, C-C, C=C, O-H either of bending or stretching nature is given in following table against each wave number in each sample. In infrared spectroscopy, there are basically two regions, fingerprint region and functional groups region. The range of fingerprint region is from 400 cm -1 to 1500 cm -1 wave number which is not analyzed usually due to its complexity, as a large number of peaks appears in that region. Each bond represents existence of a functional groups. The prepared cathodes have strong peaks in the range of 700 cm -1 to 1800 cm -1 .The peaks are attributed to C-H, C=O, O-H and C=C which are the main bonds present in oxides base cathodes. Raman spectroscopy is used to detect vibrational, rotational, and other states in a molecular system, capable of probing the chemical composition of materials. For samples BLCZ (S1) peaks are found at 157, 525, 957 and 1363 cm -1 . The peaks at 157 and 525 cm −1 wavelengths are analogous to O-B-O typical vibrations. The peak at 957 cm −1 wavelength correspond to B-O bonds stretching vibrations. For samples SLCZ (S3) peaks are found at 141, 296,649, 939, 1086 and 1344 cm -1 . The peaks at 141, 296 and 649 cm −1 wavelengths are analogous to O-B-O typical vibrations. The peaks at 939 and 1086 cm −1 wavelength correspond to B-O bonds stretching vibrations. Furthermore, for the Raman spectra of single Perovskite LSCF there is no mode vibrations in the range of 200–500 and 700–900 cm −1 can be found except (S2), which are xi demonstrative of double Perovskite structures LSCF materials. Therefore, the outcomes of the Raman spectral study agree well with those of literature, which showed that both the rhombohedra structure and double Perovskite phase are from space group R3C. So S1, S2 and S3 will behaves as an excellent cathode material as generating more oxygen ion vacancies which enhance the oxygen reduction reaction (ORR) at the cathode side. The electrical DC conductivity of prepared cathodes BaLaCoZn, CaLaCoZn and SrLaCoZn were measured by two probe method in the temperature range of (300-600) o C in the presence of methane as a fuel in air environment. The synthesized cathode material (S1) has maximum conductivity of 10.12 Scm -1 at 600 °C and the synthesized cathode material (S2) has minimum value of 3.3 Scm -1 at 300 °C.