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.
Browse
3 results
Search Results
Item Fabrication and Characterization of Zinc Sulfide and Natural Fibers Based Flexible Composite for Energy Storage Application(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) Muhammad Ansar; CIIT/SP19-RPH-018/LHR; Dr. Muhammad Aamir Razaq; LHR TP 7255Metal Sulfides are commonly employed as an electrode for energy storage applications due to versatile characteristics of high-power density and cycling stability in comparison of metal oxides. Among metal sulfides, zinc sulfide is promising due to facile synthesis and wide potential window. However, zinc sulfide based electrodes are limited to employ in modern bendable/flexible energy storage devices due to inherited rigid structure. Lignocelluloses (LC) fibers known as natural fibers can incorporate flexible matrix for zinc sulfide nanostructure to develop flexible and environmentally safe paper electrode for energy storage applications. Presented research shows successful fabrication of zinc sulfide nanostructure via facile microwave assisted method and developed bendable ZnS/LC composite paper sheets. Furthermore, fabricated composition sheet is successfully prepared and analyzed by X-ray diffraction (XRD, Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, Cyclic voltammetry (CV) and Galvanostatic charge discharge (GCD) characterizations for energy storage applications.Item Extraction of Carbon Based Biochar fromWasted Biomass for Energy Storage Application(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Aftab Javid; CIIT/FA23-RPH-003/LHR; Dr. Muhammad Aamir Razaq; LHT TP 9838The growing need for powerful eco-friendly energy storage has determined research into better electrode materials for supercapacitors. Supercapacitors famous for their fast charge and discharge cycles and high-power output, but their energy storage capacity remains relatively low, when relying on Bismuth Sulfide (Bi₂S₃). To solve this, we use Biochar, a carbon-rich material that can both store more electrons and also facilitates fast electron transport. In this study, we created a binder-free electrode by growing Bi₂S₃ directly onto Biochar made from Amal Tass pods biomass waste, using a fast microwave-assisted process. First, we turned the Amal Tass pods into conductive biochar through drying, grinding, and a simple hydrothermal step. Then mixed this biochar into water with Bi(NO₃)₃·5H₂O and thiourea, and exposed the mixture to microwave energy and a uniform Bi₂S₃–Biochar composite formed, no binders or extra additives needed. This composite delivers a high energy density, making it a strong candidate to replace batteries. Raman spectroscopy confirmed that Bi₂S₃ adopted its orthorhombic crystal structure within the carbon matrix, and it also showed the characteristic D- and G-bands of biochar at 1391 and 1595 cm⁻¹. When we tested the composite in 2 M KOH, cyclic voltammetry revealed clear redox peaks whose areas raised with scan rate, indicating strong pseudocapacitive behavior. Electrochemical impedance spectroscopy showed low charge-transfer resistance, which means ions and electrons move through the material with ease. Together, these results demonstrate that our quick, green microwave method produces Bi₂S₃–Biochar electrodes that combine high power with improved energy storage an encouraging step toward the next generation of sustainable pseudocapacitors.Item Synthesis and Characterization of Magnesium- Based Metal Organic Framework (MOFs) for Energy Storage Application(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Shahzad Safdar; CIIT/FA23-RPH-039/LHR; Dr. Muhammad Aamir Razaq; LHR TP 9865This research presents the sustainable synthesis of magnesium-based metal-organic framework (Mg-MOFs) composites integrated with lignocelluloses (LC) fibers derived from corn husk via a hydrothermal method route using Mg(NO₃)₂·6H₂O and H₃BTC as precursors. Magnesium was utilized because it is abundant, environmentally friendly, less reactive, cost-efficient, and an electrochemically compatible material. The resulting Mg-MOFs/LC composite harnesses the synergistic benefits of both components—magnesium offers lightweight characteristics, moderate electrical conductivity, and structural integrity, while lignocelluloses fibers provide biodegradability, flexibility, and environmental safety. Structural and optical characterizations confirmed successful composite formation. UV-Visible spectroscopy revealed enhanced light absorption with notable π→π* transitions and a red-shifted absorption edge (2.73 eV), showing strong interfacial electronic coupling. Raman spectroscopy found key vibrational modes, including Mg–O bonds and aromatic linker structures, alongside preserved organic functionalities. Electrochemical assessments showed that cyclic voltammetry shown pronounced redox activity with a high area under the curve. Although the specific capacitance of Mg-MOFs is 122 F/g but a reduction in specific capacitance was seen with LC incorporation, galvanostatic charge- discharge measurements proved extended discharge times and strong redox behavior, highlighting effective charge storage and diffusion. The EIS of composite show the less resistance as compared to Mg-MOFs. With its eco-friendly fabrication, mechanical resilience, and promising energy storage performance, the Mg-MOFs/LC composite appears as a practical material for next-generation flexible and biodegradable supercapacitor applications.