Department of Physics
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Item Synthesis of Nickel Oxide (NiO) Fluorescence Nano Quencher and Their Application in Aptasensing of Ochratoxin-A(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2019) Aqsa Khan; FA17-RPH -042; Dr. Rizwan Raza; LHR TP 5727The fabrication of fluorescence based biosensor for the ultra-sensitive and selective monitoring of Ochratoxin-A in the food samples is very important these days. We demonstrate for the first time, the development of nickel oxide nanoparticles (NiO) quenching based aptasensing platform for the detection of target molecule (OTA). In this work, NiO quench the fluorescence of FAM-labeled aptamer. These quenched intensities were due to energy transfer processes to the metal nanoparticles. Conversely, increase in fluorescence quenching intensities with a decrease in the size of the nanoparticles which may be useful for the design of new analytical tool to detect the presence of target analyte. The structural properties of prepared nano materials were analyzed by X- Ray diffraction (XRD).Surface morphology of prepared metal oxide nano materials were studied by Scanning Electron Microscopy (SEM) and crystalline behaviors size/shape was analyzed by RAMAN spectroscopy. We have found the cost-effective, easy to use and affordable method to design aptamer based fluorescence quenching assay for the detection and early diagnoses of mycotoxins (OTA).Item The Alkali (Li, Na) Based Solid State Ion Conductors Electrolytes for Solid State Batteries(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) ALEEMA MASOOD; CIIT/FA20-RPH-022/LHR; Dr. Rizwan Raza; LHR TP 7983Initially, the energy storage devices based on liquid electrolytes are widely used to provide the continuous channel for energy transportation. Some drawbacks are (environmentally harmful and thermally unstable) that limits their commercial applications. While considering environmental aspects, the researchers move to find the environmental friendly, and thermally stable solid state electrolyte based energy storage devices. In this era, the solid state batteries become a center piece of research as the foremost candidate with great safety concern, high energy densities, cost effective and environmental friendly. In solid state batteries, the alkali based garnet type solid state electrolyte materials are thermally stable, eco-friendly, and have high energy density. In modern world, the consumption of lithium ion batteries surge day by day. There are limited raw resources for lithium, therefore researcher move to stir up to find alternative of lithium. Sodium can be considered as the best alternative of lithium. However, sodium is one of the most abundant element in the earth crust. In this research, alkali based garnet type solid state electrolyte as Li7La3Zr2O12 and Na2La3Zr2O12. The main objective of this work is to examine the ionic behavior, homogeneity, porosity, effect for the slid sate batteries. The x-rays diffraction is used to study the crystal structure of the material. The phase of the synthesized material is examined by high score expert. The prepared material is garnet type material with space group Fd-3m. The scanning electron microscopy is used to analyze the morphology of the synthesized electrolyte materials. The cyclic voltammetry and AC impedance spectroscopy are used to determine the charging and discharging rate, and ionic behavior of the materials. The ionic conductivity of both materials has comparable value for Li7La3Zr2O12 observed at room temperature 2.39×10 -6 Scm -1 . The optical band gap of both synthesized materials is analyzed by ultra violet visible spectroscopy. The Raman spectroscopy technique is used to determine the vibrational energy modes of both synthesized materials.Item Electronic Structure and Energy Application of Layered Carbide Materials(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) Maria Sarfraz; CIIT/FA20-RPH-015/LHR; Dr. Rizwan Raza; LHR TP 7978This project prepares the silicon carbide and MgZnO-based semiconductor materials for photocatalysis applications. An efficient photocatalytic material is required for proper working to enhance the efficiency of clean energy devices. The efficiency of photocatalysis water-splitting reaction has been limited. However, carbide and zinc oxide-based catalysts are developed to address such issues and discuss the reaction mechanism. Therefore, in this research work, SiC composite is made by hydrothermal method while MgZnO semiconductor materials are made by sol-gel method. To analyze the synthesized samples' structural properties, XRD has been carried out and find out SiC composite and MgZnO materials. RAMAN and UV spectroscopy is used to detect vibrational, rotational, and other states in a molecular system, and materials' optical properties have been studied, respectively. Further, electrochemical characterizations include EIS, Linear sweep voltammetry, and cyclic voltammetry. It has been observed that both materials are actively involved in electrochemical reactions. It can be concluded that the best performance among the two prepared samples is given by the model MgZnO. The reason is that MgZnO behaves like a promising photocatalyst compared to that SiC. Theoretical studies have been performed using Density Functional theory calculations to study the optical parameters, electronic structure, the density of states, and band gapItem Recycling of Laptop Spent Li-Ion Batteries and Characterization of Extracted Materials(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) Zarmeena Akhtar; CIIT/SP20-RPH-064/LHR; Dr. Rizwan Raza; LHR TP 7728The run to meet the dire energy needs continue till more smart devices are introduced. The speedy consumption of LIBs for portable smart devices i.e. Laptops, Tablets, cell phones and electric auto mobiles give rise to increased number of discarded batteries. Discarded LIBs involves poisonous chemicals and hazardous heavy metals that cause a significant minace to ecosystems. It is mandatory for environmental protection and economic aspects to re-process these LIBs by efficient process. The current focus of much research is establishment of recycling process of LIBs. However, consequential research remains to improve the technique. In my research work different valuable materials like lithium and cobalt will be extracted by diverse methods like Thermal treatment and Leaching process. The experimental calculations of extracted material will be done. The analysis and characterization will be done to study the different parameters of extracted material.Item Synthesis of M1+xAlxTi2-x (PO4)3 (where M=Li or Na) Based Electrolyte Materials for Solid State Batteries and Study of their Electrochemical Properties(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) Zunaira Zulfiqar; CIIT/FA20-RPH-041/LHR; Dr. Rizwan Raza; LHR TP 7997As "Necessity is the mother of invention", energy is stored from primary sources and released out, for consumption when there is a shortage of energy, to balance the life of human beings. In the modern world, sensational research has been done to design storage devices. While considering cost and environmental aspects, the researcher is impatient to find a friendlier environment and portable energy storage devices. The desire for environment-friendly and portable energy storage devices has steered the thorough investigation for all-solid-state rechargeable batteries. Solid state batteries have got attention because of more energy security and long life. Phosphate-based ceramic electrolytes are promising candidates for solid state electrolyte- based lithium and sodium-ion batteries. Sodium-ion batteries can potentially hold energy comparable to that of commercial lithium-ion batteries. Li resources are limited whereas sodium is one of the most abundant elements in the Earth’s crust. Rechargeable sodium cells are the ideal alternative to lithium-ion batteries based on material abundance and standard electrode potential. In this work, phosphate-based solid state electrolytes as M1+xAlxTi2-x (PO4)3 where M= Li, Na, and x = 0.5, are synthesized by solid state reaction and ball milling method. The main objective of this study is to examine the ionic behavior, homogeneity, porosity, crystal structure, and band-gap and also to determine the charging and discharging rate of the prepared material. The crystal structure of synthesized powder is examined by the x-rays diffraction technique. X pert high score software is used to determine the phase of the prepared material. Synthesized material has a single crystalline phase same as NASICON type material with space group R3̅c. Microstructure analysis is done by using scanning electron microscopy. The porosity of solid-state electrolytes is determined by the Archimedes method. The charging and discharging rate are examined by electrochemical techniques (AC-impendence-conductivity, cyclic voltammetry). The ionic conductivities of both have the same exponential value with 2.09×10-3 and 1.96×10-3 at 25°C, respectively. Ultraviolet spectroscopy is done to examine the band-gap. Tauc plot is used to determine band-gap for Li1.5Al0.5Ti1.5 (PO4)3 and the Na1.5Al0.5Ti1.5 (PO4)3. Raman spectroscopy is used to determine the vibrational energy modes of the prepared materialItem Electrochemical Interfacial Studies of Heterogeneous Catalysis for Biogas fueled Solid Oxide Fuel Cell(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) Shahzad Rasoo; CIIT/SP20-RPH-053/LHR; Dr. Rizwan Raza; LHR TP 7699Solid oxide fuel cell (SOFC) is an energy conversion device that directly converts the chemical energy of biogas/methane (fuels) into electricity. When using biogas/methane as a fuel, the traditional nickel-based anode is required to improve SOFC performance. While impressive growth has been made in the development of other anode materials, nickel-based anodes with high catalytic activity for biogas/methane fuels are still the promising anode for the commercialization of SOFCs. The nickel, copper, and ceria-based anode have been verified as an effective way to increase the performance and long-term stability of hydrocarbon-based SOFC. Thus, to improve the catalytic activity (NiCu)xCe1-xO and NiCu1-xCexO anode materials are synthesized. The prepared materials are (NiCu)xCe1-xO and NiCu1-xCexO where (x=0.2, 0.4, 0.6, 0.8, 1) using solid- state method. The structural analysis is studied through X-Ray Diffractometry (XRD). The average crystallite size of all materials ≈ 28 nm. The XRD pattern of (NiCu)xCe1-xO and NiCu1-xCexO describes that oxide materials have multiphase which shows the heterogeneous nature. The XRD patterns also confirmed that the biogas/methane used as fuel show good results for prepared samples. The important structural properties of the samples are analyzed using Fourier transform infrared (FTIR) spectroscopy and the data recording range is 4000-500 cm-1. Raman spectroscopy detects vibrational, rotational states in a molecular system, capable of analyzing the chemical composition of materials. The electrical conductivity was measured with a KD2531E low resistance ohmmeter and the maximum conductivity is obtained 8.43 Scm-1at temperature 650 ℃. The activation energy of samples is also calculated. The asymmetrical three layers cells are fabricated for testing of fuel cell performance in the temperature range of 400-600 ℃ biogas/methane as a fuel. The maximum OCV was obtained 1.52 V at 600 ℃. .Item Theoretical and Experimental Study of Mixed Ionic Electronic Materials (MIEC) for Electrochemical Functional Nano-Composite Layer(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2017) Muhammad Khurram Qureshi; CIIT/FA15-RPH-014/LHR; Dr. Rizwan Raza; LHR TP 6984Due to the increased demand of energy there would be a stern dispute in the near future as the efficient energy resources are soon to be ceased. To overcome such a challenging disagreement, we have to put our attention towards such novel energy conversion and efficient technology which can strengthen us against such problem. Fuel cells are promising devices for clean and efficient power generation. The electrolyte free fuel cell (EFFC) is an innovative, high-energy conversion and efficient generation of fuel cells which directly convert the chemical energy into electrical energy. In this research the mixed ionic and electronic conducting material will be equipped by desired route for EFFC production. MIEC is basically responsible for the performance of EFFC. EFFC with only one homogenous layer Nano-composite material comprises upon ionic and electronic conductors which will overwhelm the mechanically and chemically compatible issues. The designed material was examined experimentally and theoretically. The single homogenous layer consist upon mixed conducting Nano-composite material certifies the better performance, high efficiency and reliability. Diverse electrochemical measurements are used to investigate the performance and efficiency of prepared EFFC material. The conductivity of MIEC is investigated with 2 probe and 4 probe method. After that, the mixed conductivity was separated out with the help of ion blocking and Heb-Wagner method. These two techniques were used to study the ionic and electronic conductivity of MIEC. Similarly, the optical, mechanical, vibrational, structural characteristics and important parameters were investigated with the help of multiple techniques The working and electrochemical performance of prepared EFFC was studied at Nano level to explain the working principle of as prepared EFFC. Theoretical model and simulations of pItem DEVELOPMENT OF ELECTRODE MATERIALS FOR FUEL CELL USING PULSED LASER DEPOSITION(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2017) IMRAN ALI; CIIT/SP15-RPH-012/LHR; Dr. Rizwan Raza; LHR TP 6845The prevailing energy crisis in the world has to be tackled by employing sustainable energy sources. In recent years, research has been conducted on solid state ionic devices such as fuel cells, lithium ion batteries and solar cells which could be the future alternate energy storage and conversion technologies with no environmental issues. It has been observed that solid oxide fuel cells SOFCs with electrodes layers on electrolyte using Pulsed Laser Deposition PLD as compared to other fuel cells yield better results i.e. they can operate at intermediate temperature have high conductivity and enhanced power density. This thesis gives an approach to develop nanocomposite electrode materials for SOFCs to lower the operating temperature of SOFC. Lithium Nickel Copper Oxide (LNC), Lithium Nickel Copper zinc Oxide (LNCZ) and Samarium doped Ceria (SDC) nanocomposite have been synthesized using solid state reaction method and wet chemical method. The structure and morphology of nanocomposite electrode was examined by X-Rays Diffraction (XRD) and scanning electron microscopy (SEM). Atomic Force Microscopy (AFM) is used to examine the roughness and surface morphology of pulsed laser deposited film. The fuel Cell Performance was tested at temperature (550-7000 C). The Conductivity of the sintered nanocomposite measured by a two probe DC method. XRD pattern of the samples show that the materials are nanostructures. SEM images expose the morphology of materials which are homogenous and porous. Electrochemical study of synthesized fuel cell shows a mixed conductivity of 1.3 Scm-1 at 6500C. The electrochemical Performance of LNC/SDC/LNC configuration was measured with OCV 0.80V, Current density 400 mAcm-2 and power density 108 mW/cm2 with hydrogen fuel at 6500C. Whereas OCV 0.80V, Current density 408mAcm-2 and power density 118 mW/cm2 were observed at 6500C for LNCZ/SDC/LNCZ configuration using hydrogen as fuel and air as reduction agent at cathode terminal.Item Direct Internal Reforming of Methane Fueled Solid Oxide Fuel Cell by Effective Catalyst(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2017) MUHAMMAD UMAIR; CIIT/SP16-RPH-001/LHR; Dr. Rizwan Raza; LHR TP 6994Fuel cell is a device that produces power through chemical reaction without combustion. It is more effective among other source of energy. It is an environment friendly low or zero emission, high productivity, multi-fuel capacity, versatility. In this project, the work is done on the catalytic study of Solid Oxide Fuel Cell (SOFC). In SOFC, the most commonly materials are used ceramic based materials e.g. for electrolyte Yttria-Stabilized Zirconia(YSZ) but it require high working temperatures (700– 1000 °C) and can be keeping running on different fuels including natural gas. In this project, the electrode (LiNiCuZnFeO) is prepared by Solid State Reaction (SSR) method. The compatible electrolyte (LNK-SDC) is prepared by co-precipitation method. Three catalyst of different molar ratio of Barium Nickel Cobalt [Sample no.1 (Ba0.2Ni0.4CO0.4O3), Sample no.2 (Ba0.2Ni0.6CO0.2O3), Sample no.3 (Ba0.2Ni0.2CO0.8O3)] are prepared for direct internal reforming of SOFC using sol-gel method. Natural gas is used as a fuel for SOFC. The best performance of the cell is achieved at 650℃ with Sample no.2 (Ba0.2Ni0.6CO0.2O3) with maximum open circuit voltage (OCV) of 0.7V, current density of 250 mAcm-2 and power density of 64mWcm-2 with highest conductivity of 0.42 S/cm.Item Synthesis of Catalyst for Direct Ethanol Fuel Cell and its Electrochemical Characterizations(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2018) NAZIM ALI EJAZ; CIIT/SP16-RPH-004/LHR; Dr. Rizwan Raza; LHR TP 6910Fuel cell is a device which uses to generate electric current by chemical reaction without any kind of combustion and noise. It is environmental friendly and more efficient among all the other energy devices. Now the increasing interest of direct alcohol fuel cell (DAFC) is emphasized as an alternate source of clean, cheap, reliable and minimal environmental impact energy. Mostly methanol is used as a fuel but due to its toxicity, alternatively ethanol is used as a fuel due to its some advantages like nontoxic and its availability from biomass resources. In this research, a suitable catalyst for direct ethanol fuel cell (DEFC) is synthesized, which increase the rate of oxidation of ethanol into CO2. The purpose of this work is to reduce the poisoning effect which will increase the activity of electrode. The operating temperature of direct ethanol solid oxide fuel cell (DESOFC) is within the range 600-1000°C. Three samples with different molar ratio are prepared Li0.1Ni0.5Cu0.1Ce0.3 oxides, Li0.1Ni0.5Cu0.2Ce0.2 oxides and Li0.1Ni0.5Cu0.3Ce0.1 oxides by sol-gel method. The best results are shown by Li0.1Ni0.5Cu0.1Ce0.3 oxides the highest conductivity is 0.27 S/cm at 750°C and power density 20 mWcm-2 at 700°C observed.