Browsing by Author "Dr. Faiza Mustafa"

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Metal Organic FrameWork Encapsulated Luminous Quantum Dots Functional Composite for OptoelectronicApplications
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Arshia Manzoor; CIIT/FA23-RPH-045/LHR; Dr. Faiza Mustafa; LHR TP 9868
Metal-organic frameworks (MOFs) offer substantial structural benefits and outstanding application in numerous industries, due to their huge specific surface area, high porosity, open pore structure, and easily changeable and functionalized porous surface. However, MOFs by themselves have several limitations, including low stability, set pore size, and restricted electrical conductivity. The innovative incorporation of QDs into MOF structures can get beyond these restrictions. While the host (MOFs) framework offers optimal connections to the guest (QDs) for improving stability, extended carrier lifetime, improved, greater photoluminescence quantum yield, and synergic features, the resulting host-guest structure exhibits a wide variety of synergetic qualities. In this research project novel Zif-67@ZnSe-QDs composites are synthesized by facile wet chemical method. The photoluminescence spectroscopy technique was employed to explore the optoelectronic applications focusing on luminescence/sensing properties of the synthesized composites. The UV-visible spectroscopy was done to estimate the band gap of the composites. The crystallographic structure of the composites was studied using XRD. FTIR and Raman spectroscopy was used to examine the vibrational modes and functional groups of the materials. SEM analysis was used to determine the morphology of the samples.
Multicomponent Photoluminescence Emission Tuning in Ternary Quantum Dots (TQDs) Via Dopant Interaction
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Ayesha Iram; CUI/SP23-RPH-018/LHR; Dr. Faiza Mustafa; LHR TP 9638
AgInS (AIS) QDs, among TQDs, have enormous potential to replace traditional II–VI QDs due to their long fluorescence lifetimes, significant Stokes shift, low toxicity, high attenuation coefficient, and exceptional optical properties in the visible to near-infrared range. With prolonged use, the combined materials unavoidably showed an undesired shift in spectrum due to their differing optical and UV stability. Thus, it is essential to build single-phase full-spectrum QDs. Single phase full spectrum QDs for the creation of white light have recently been described for Cu and Mn doped TQD base luminescent materials. The structural, optical and electronic properties are analyzed by UV-Visible, XRD, Raman and Photoluminescence spectroscopy. In this research project, AgInS quantum dots has been successfully synthesized by hydrothermal method, Raman spectroscopy results show the vibrational modes of AgInS, Particle size of AgInS(8nm), Cu(8.9nm), Mn(10nm), Cu- Mn(6nm) measured by XRD. Due to its greatest thickness and minimal lattice misfit, AgInS is discovered to have a wide photoluminescence spectrum, which indicates that its photoluminescence intensity has grown and covered all structural faults. Thus, I found that the Cu/Mn-AgInS sample's PL spectrum shows several emission peaks, indicating the existence of different radiative recombination processes.
Performance Evaluation of Fe-Doped ZnO Nanostructures Embedded in PVA Matrix for UV- Shielding
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Maryam Akram; SP23-RPH-028; Dr. Faiza Mustafa; LHR TP 9645
It is well known that ultraviolet (UV) radiation can cause health issues that can show up temporarily as well as permanently. UV radiation is linked to skin cancer, sunburns, ageing, and other disorders. Thus, there is a great deal of interest in research about the development of UV-shielding materials for a variety of uses, including UV-light resistant packaging, sunscreens, contact lenses, coatings, and even clothing. Among UV-shielding materials ZnO demonstrates strong photoresponse in UV absorption, an essential need for photon-trapping applications. Doping is a crucial strategy to improve the UV-visible absorption property through defect engineering. Due to their significant UV-attenuating capabilities, doped ZnO-based materials are recognized to provide certain advantages over pure ZnO, which supports its candidature as UV-shielding material. Polar organic polymer polyvinyl alcohol, or PVA, has gained a lot of interest recently because to its exceptional mechanical flexibility, high chemical and thermal stabilities, affordability, non-toxicity, and outstanding biocompatibility. The distribution of the nanocomposite inside the PVA matrix allows for modification of the material's optical properties. In this study, we are developing Fe-doped ZnO embedded in PVA matrix via facile wet chemical technique. We are evaluating the UV-shielding performance of the synthesized nanocomposite by UV vis absorption spectroscopy technique. We are analyzing the crystallographic structure of the nanocomposite via XRD. We are studying the vibrational and functional groups via Raman and FTIR spectroscopy techniques respectively. We are using SEM to study the morphology of the composites.
Preparation and Characterization of Conjugated Co- ZnO/GO Nanocomposite for Photocatalytic Applications
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Aiman Sadiq; CUI/SP23-RPH-016/LHR; Dr. Faiza Mustafa; LHR TP 9636
Zinc oxide (ZnO), an n-type semiconductor, has shown great promise as a robust photochemical catalyst because of its simplicity of manufacture, high chemical stability, low toxicity, and outstanding oxidation capacity. This is especially true for applications requiring electrical components, the eradication of microorganisms, and the breakdown of organic contaminants.However, photocatalysis efficiency is decreased by the quick recombination of photogenerated charge carriers. Enhancing the transmission of photogenerated electrons through the construction of a composite and the addition of a cocatalyst are two practical methods for raising photocatalytic efficiency. By creating surface defects, doping ZnO nanoparticles can increase optical absorbance in the visible light spectrum. Because of its sp2-hybridized carbon atoms, graphene and its derivatives, graphene oxide (GO) and reduced graphene oxide (rGO), may function as a substrate, an electron-transporting substance, and a photocatalyst.In this project we have synthesized Co-ZnO/GO nanocomposite via facile wet chemical method. The structural properties of the materials were studies via Raman and XRD analysis. The band gap of the synthesized nanocomposites were estimated using tauc equation the band gap varies (3.0eV to 3.4eV) from in the UV region. The photocatalysic degradation efficiency of the Methylene Blue (MB) were recorded 93% to 99% by using UV-visible Spectroscopy.
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 10115
Stimuli-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.
Systematic Interfacial Strain Induced Tuning of Structural and Optical Properties of Ecofriendly ZnSe/Bi2X 3 (X=S, Se, Te) Core/Shell Quantum Dots
(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2024) Saleha Amjad; CIIT/FA22-RPH-034/LHR; Dr. Faiza Mustafa; LHR TP 9428
Zinc selenide-based Core-Shell QDs are generating many recognitions because of its ability in many applications such as optoelectronic and display devices. Similarly, Bismuth chalcogenides Bi2X3(X= S, Se, Te) are a class of unique material that are widely used for optoelectronic applications due to optical, electrical properties and eco-friendly composition. In this work Novel ZnSe/ Bi2X3(X= S, Se, Te) based quantum dots of core and shell were manufactured via facile two step method of hot injection. The structural, optical and electronic properties are analyzed by UV-Visible, XRD, Raman and Photoluminescence spectroscopy. The core (ZnSe) and shell modes Bi2X3 (X= S, Se, Te) vibrational modes properties are displayed in the Raman spectroscopy data. data. ZnSe/Bi2Se3 has 1.7% lattice mismatch, ZnSe/Bi2Se3 has 31.9%, and ZnSe/Bi2Te3 has 15%, according to X-ray diffraction data.The ZnSe/Bi2S3, ZnSe/Bi2Se3, and ZnSe/Bi2Te3 thicknesses as seen by XRD are 10.8, 1.54, and 3.49nm, respectively. The average size of a ZnSe particle is 41.37 nm, while the core-shell particles of ZnSe/Bi2S3, ZnSe/Bi2Se3, and ZnSe/Bi2Te3 are 9.8, 4.7, and 8.4 nm, in that order. XRD is used to measure these computations theoretically. Due to its greatest thickness and minimal lattice misfit, ZnSe/Bi2S3 is discovered to have a wide photoluminescence spectrum, which indicates that its photoluminescence intensity has grown and covered all structural faults. Thus, I found that ZnSe/Bi2S3 is the most appropriate material for Core-Shell QDs out of the three bismuth chalcogenides ZnSe/Bi2X3 (X= S, Se, Te).