M.Phil / MS
Permanent URI for this collectionhttps://repository.cuilahore.edu.pk/handle/123456789/60
This collection archives the complete set of theses produced by students of the COMSATS University Islamabad, Lahore Campus.
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Item Stimuli Responsive PANI Based Composites for Optical Sensing Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Usman Jamil; CIIT/FA23-RPH-040/LHR; Dr. Faiza Mustafa; LHR TP 10115Stimuli-responsive polymeric materials have emerged as powerful platforms for next- generation optical sensing technologies due to their tunable physicochemical properties and rapid response to environmental changes. In this work, polyaniline (PANI)-based composites were synthesized and engineered to exhibit sensitivity toward external stimuli such as pH, light, and chemical vapors. PANI was selected as the primary functional component because of its inherent redox activity, environmental stability, controllable conductivity, and strong optical transitions in the UV-Vis region. To enhance its sensing performance, PANI was incorporated into composite structures with carbon-based nanomaterials and biodegradable supports, providing improved surface area, enhanced charge-transfer pathways, and higher optical response. Structural characterization through FTIR, XRD, and Raman spectroscopy confirmed successful composite formation and preserved PANI backbone vibrations. UV-Vis spectroscopy demonstrated distinct π→π* and n→π* transitions, accompanied by measurable shifts in absorbance intensity as a function of pH and analyte concentration, validating the composite’s optical sensitivity. Raman spectroscopy further revealed changes in vibrational modes associated with protonation and deprotonation, indicating rapid and reversible responsiveness to chemical stimuli. Optical sensing experiments showed that the PANI-based composite exhibited high sensitivity, stability, and repeatability, particularly in pH-triggered optical modulation, making it an excellent candidate for real-time environmental and biochemical sensing. The results highlight that stimuli-responsive PANI composites offer a cost-effective, flexible, and highly tunable platform for optical sensing systems. Their robust performance positions them as promising materials for future smart sensors, environmental monitoring tools, and optical detection devices.Item Synthesis and Characterization of Metal and Natural Fibers Based Bendable Electrodes for Zinc Ion Battery Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Sheeza Musarrat; CIIT/SP24-RPH-008/LHR; Dr. Muhammad Aamir Razaq; LHR TP 10121This study aims to address the inherent limitations of conventional zinc-ion batteries (ZIBs) through the development of flexible and mechanically robust zinc-derived composite electrodes suitable for affordable, eco-friendly, and high-performance energy storage systems. Owing to their low cost, high safety, non-flammable aqueous electrolytes, environmental benignity, and high theoretical capacity, zinc-ion batteries have emerged as promising alternatives to lithium-ion batteries for next-generation energy storage applications. Despite these advantages, the intrinsic brittleness and limited mechanical flexibility of zinc-based electrodes restrict their practical implementation in flexible, lightweight, and wearable devices. To overcome this challenge, current research efforts are directed toward reinforcing active materials with natural fibers(NF)/lignocelluloses (LC) to construct composite electrode architectures. This strategy preserves the favorable electrochemical characteristics of zinc while simultaneously imparting mechanical flexibility, structural integrity, and deformation tolerance. In this work, NF-reinforced composite electrodes with different doping were synthesized and optimized using co-precipitation process. The resulting NF-reinforced composite electrodes exhibited significantly improved mechanical robustness without sacrificing electrochemical performance, thereby advancing their suitability for flexible and wearable zinc-ion battery applications. Beyond demonstrating the feasibility of NF-integrated flexible ZIBs, this study also examines the effect of different doping on the structural and electrochemical properties offering a sustainable and scalable pathway for enhanced next- generation electrode manufacturing.Item Synthesis and Characterization of Ag Based Flexible Paper Electrode for Energy Storage Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Ishmal Irfan; CIIT/SP24-RPH-010/LHR; Dr. Muhammad Aamir Razaq; LHR TP 10122The need for sustainable energy technology is fueled by the growing reliance on fossil fuels, which has resulted in significant environmental issues and resource depletion. Even though the use of renewable energy sources is growing quickly, reliable and effective energy storage systems are necessary for their successful implementation. Supercapacitors extended cycle life, high power density, and quick charge-discharge capability have made them attractive options. The creation of flexible and sustainable electrode materials by turning environmental trash into components with added value for energy storage applications is the main goal of this thesis. Co-precipitation was used to create silver oxide (Ag2O) nanoparticles, which demonstrated outstanding electrochemical performance, reaching a specific capacitance of 801 F·g⁻¹ at current densities close to 12 A·g⁻¹. A binder-free, three-dimensional, free- standing Ag-based flexible paper electrode was created by using natural fibers generated from banana peels as an inexpensive and renewable substrate for the direct development of Ag2O nanoparticles. The resultant LC/Ag2O composite electrode (1:1 ratio) showed outstanding cycle stability, low charge-transfer resistance, good rate capability, and a high specific capacitance of 623 F·g⁻¹. Ag2O was successfully formed and uniformly integrated inside the fibrous matrix, as validated by structural, morphological, optical, and chemical characterization utilizing XRD, Raman, UV-Vis, FTIR, and SEM. For next-generation flexible and wearable supercapacitor applications, the new flexible electrode architecture highlights a scalable and environmentally sustainable approach by providing effective ion transport and mechanical robustness.Item Fabrication of Metal Oxide Based Charge Transport Layer for Energy Conversion Devices(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Kainat Ishtiaq; CIIT/SP24-RPH-011/LHR; Dr. Ishrat Sultana; LHR TP 10123Energy conversion devices such as perovskite solar cells, dye-sensitized solar cells, and electrochemical energy storage systems have gained significant attention due to their potential to provide efficient, low-cost, and sustainable alternatives to conventional energy technologies. A critical factor influencing the performance of these devices is the charge transport layer, which governs charge extraction, transport, and recombination processes at the interfaces. In this study, nickel oxide (NiO) and zinc oxide (ZnO) were synthesized and investigated as hole transport and electron transport materials, respectively, along with their LC sheet–based composite counterparts, for application in energy conversion and storage devices. NiO and ZnO nanoparticles were successfully synthesized using a simple and cost-effective coprecipitation method, while LC sheet–based composites were developed using corn fiber as a sustainable carbon source to enhance electrical conductivity and interfacial contact. The structural, electrochemical, and vibrational properties of the prepared materials were systematically characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and Raman spectroscopy. CV analysis revealed that pristine NiO and ZnO exhibited pseudocapacitive behavior due to reversible redox reactions, whereas LC sheet–based composites showed predominantly capacitive behavior with improved rate capability, reversibility, and charge–discharge performance. The enhanced electrochemical performance of the composites is attributed to the conductive carbon network provided by the LC sheet, which facilitates rapid electron transport and efficient ion diffusion.Item Advancing Breast Cancer Detection: Embedding Nanoparticles into Breast Phantoms for Diagnostic Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) MISBAH ASHIQ; CUI/SP24-RPH-012/LHR; Dr. Naima Amin; LHR TP 10124In this study, a single-layer homogeneous breast tumor phantom was developed to simulate the diagnostic properties of malignant breast tissue, with the aim of enhancing breast cancer detection and diagnostic accuracy. The tumor-mimicking phantom was fabricated using an optimized gelatin-based hydrogel, incorporating additives such as NaCl, PVA, glycerin, agar, ethanol, and PEG to reproduce the physical consistency and imaging characteristics of tumor tissue. Silver oxide (Ag₂O) and iron oxide (Fe₃O₄) nanoparticles were synthesized using controlled chemical methods and characterized using FTIR, XRD, and SEM to confirm their chemical composition, crystalline structure, and surface morphology, ensuring their suitability for diagnostic imaging applications. The nanoparticles were uniformly incorporated into the tumor phantom through a premixing approach, resulting in a homogeneous distribution that simulates nanoparticle-enhanced tumor tissue. The fabricated tumor phantoms were evaluated using computed tomography (CT) to assess their effectiveness in breast cancer detection. CT imaging demonstrated increased Hounsfield Unit values due to the high atomic number of silvers in Ag₂O nanoparticles, leading to enhanced X-ray attenuation, while MRI scans revealed clear signal suppression and contrast variation in Fe₃O₄- loaded phantoms owing to their superparamagnetic properties. The results confirm that the developed single-layer homogeneous tumor phantom provides a reliable and reproducible model for evaluating nanoparticle-assisted breast cancer detection and precise diagnosis, offering a simplified yet effective platform for imaging system calibration, contrast agent assessment, and preclinical diagnostic studies.Item 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 10120Among 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.Item Hydrothermal Synthesis of Nickel Manganese Ferrite (Ni0.5Mn0.5Fe2O4) and Cerium Oxide (CeO2) for Energy Storage Applications.(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Wajeeha Sajid; CIIT/FA23-RPH-050/LHR; Dr. Muhammad Asif, 60; LHR TP 10117This work presents the synthesis and characterization of a Ni0.5Mn0.5Fe2O4-CeO2 nanocomposite which is an improvement on the electrochemical performance of super capacitors. The composite has been prepared via co-precipitation route and its properties are determined by XRD, which verified the coexistence of spinel ferrite and fluorite CeO2 phases without having distorted structures. The Scherrer equation was used to calculate the average crystallite size, which was about 38nm, which means that the morphology is Nano-crystalline. The stabilization of the particle size and enhancement of the electrical conductivity with the introduction of CeO2 was achieved by their high oxygen storage and redox properties (Ce3+/Ce4+). In 1 M KOH electrolyte, electrochemical analyses were conducted in the form of cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The electrode of Ni0.5Mn0.5Fe2O4-CeO2 was a pseudocapacitive that was very reversible and had high rate capability. The composite was able to reach an energy density of 24.4 Wh/kg with a power density of 301.02 W/kg and maintain a good stability even after recharge-discharge cycles. It is believed that the enhanced electrochemical behavior is due to synergistic ferrite/ CeO2 interactions that promote ion diffusion and charge transfer. These findings include the fact that Ni0.5Mn0.5Fe2O4- CeO2 nanocomposites are potential material to be used in high-performance energy storage and catalytic applications.Item Production of Bio-Mimetic Nanoparticles for the Detection of Ascorbic Acid(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Nazar Ali; CIIT/SP24-RPH-018/LHR; Dr. Muhammad Ashfaq Ahmad; LHR TP 10125An economical, sensitive and new approach based on colorimetric and UV- visible of ascorbic acid (AA) is developed. The mechanism of this method is the oxidation of 3,3',5,5'- Tetramethylbenzidine TMB with the material of the synthesis to create the oxidized TMB of a blue shade (ox-TMB). The ox-TMB is then reduced by the ascorbic acid leading to a decrease in the color intensity which can be both visually and quantitatively determined with the help of a UV Vis scanner. The main experimental parameters of the concentration of materials, TMB concentration, pH and concentration of the analyte were adjusted to improve sensing result. The most favorable conditions were found to be material concentration of 5µM, 0.5µM TMB and an acidic medium with a pH of 3-4. The response had a high reliance on pH indicating a change in color in an acidic conditions and no response at neutral and alkaline conditions (pH 7-11). The UV-vis absorbance at 652 nm under such optimized parameters reduced proportional to the change in AA concentration. High sensitivity was observed in the linear response in the concentration range of 2-5 nM where it had the lowest limit of 1.18 nM detection limit (LOD) and the highest limit of 3.59 nM was the quantification limit (LOQ). The technique proved to be very selective to the AA with minimum signal interference with the normal substances such as dopamine, glucose, cholesterol, urea, uric acid, amino acids, and the metal ions. The feasibility of the sensor was shown by using samples of diluted lemon and orange juice that were able to recover diluted samples of 97.98%-101.11%. To conclude, this has created sensing platform is easy, fast, accurate, and cheap, and therefore can be utilized in ascorbic acid detection in food samples and the future portable sensing platform is achievable.Item Study of Streaming Dust Acoustic Instability in Quantum Plasma(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2018) Asif Zahoor; FA16-RPH-031; Dr. Muhammad Jamil; LHR TP 5240In this thesis a study related to Streaming Dust Acoustic Instability in Quantum Plasma is done. In this investigation starting from equation of motion containing Fermi Pressure, Bohm Potential and Exchange Correlation term we use quantum hydrodynamic (QHD) model to derive a general expression for dielectric constant which led to the final dispersion relation. A graphical discussion is also made by considering real part which shows the phase speed of DAWs whereas the imaginary part give the growth rate. The graphical results are obtained by varying the mass of dust particles, number density of electrons and by taking different streaming speed. This research is expecting a great scope in astrophysical quantum plasmasItem Study of Dust Acoustic Waves with Dust Charge Fluctuation in Quantum Plasm(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2018) Rubina; FA16-RPH-016; Dr. Muhammad Jamil; LHR TP 5230In this dissertation, the time-dependent charge fluctuation of dust particles have been studied in quantum dusty plasmas. The dust acoustic wave has been taken as the perturbation of the plasma system. The quantum fluid model consisting upon momentum balance equation, continuity equation and gravitational Poisson’s equation has been employed to solve for the dispersion relation. The instability of the wave in the form of damping is observed. It is noticed that the dust acoustic wave went to damp for the whole spectrum of k on varying ion-thermal temperature, electron number density and dust radii.