Department of Physics
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Item Fabrication of Breast Cancer Phantom for the Estimation of Radiation Dose in Breast Cancer Radiotherapy(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) Sahar Khalid; CIIT/FA20-RPH-008/LHR; Dr. Naima Amin; LHR TP 7975A Gel-based breast tumor phantom was fabricated to estimate radiation dose in breast cancer radiotherapy. The materials used have similar properties to real tumor tissues. Vegetable oil was used as a source of fats and lipids in the Phantom, while Gelatinwas used as a source of protein to make equivalent breast tumor tissues. NaCl was added to increase the Phantom's conductivity. Different characterization techniques were used to analyze the equivalency of tumor phantom with real breast tumor tissues. The bonding characteristic in FTIR spectra shows different organic compositions in the Phantom. X- ray diffraction was used for structural properties to find crystalline structure in the Phantom. It shows the highest crystalline structure peak at [200] planes due to the presence of NaCl. The swelling test helped to swell the tumor phantom with the right water content equivalent to real tumor tissues. The swelling ratiowas increased until 35 minutes later, and the sample started to degrade. Degradation was used to check the life span of a phantom. 40 Gy of Radiation dose was given to the tumor phantom, which led to the breakage of ester bonds in the Phantom, similar to the breakage of phospholipids in the cell membrane of breast tumor cells after the radiation was given.Item Fabrication and Characterization study of Micro Thin Film Electrolyte for the Solid Oxide Fuel Cell (SOFC)(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) RIZWAN ASGHAR; CIIT/SP20-RPH-033/LHR; Dr. Muhammad Ajmal Khan; LHR TP 7691In this study, Calcium Doped Ceria (CDC) thin film is prepared by the two steps, in the first step calcium doped ceria (CDC) powder is synthesized by co-precipitation method and in the second step, the slurry of calcium doped ceria (CDC) with ball milling and then thin film is casting with help of Tape casting technique. The fabricated thin films were sintered in the range of temperatures (150-750) ℃, in an air atmosphere. Crystal structure revealed that thin film has a cubic fluorite structure, and its average crystallite size is in the range of (53-42) nm. Raman analysis of the thin film was done in the temperature range of 350-750℃. These results showed that CDC thin films have high oxygen vacancies as sintering temperature rises. Which was depicting the high conductivity of the thin film. These results were also verified by the Conductivity measurements. The increase in FWHM of main peaks of Raman spectra, with an increase in temperature resulting in reduction of the crystallite size. Which was also confirmed by XRD results. FTIR results showed the formation of the Ce-O bonds, OH stretching, etc. Furthermore, FTIR spectra of the thin film at various temperatures indicated that OH stretching decreased as temperature increased, indicating that moisture in the sample reduced. Uv visible analysis was done at two different temperatures, 150 and 750℃. Band gap values decreased with increase in the temperatures. It was 3.22eV at 750oC and 3.3eV at 150℃. The conductivity measurements showed that conductivity of thin film was increasing as sintering temperature rises. which was confirmation of Raman results. Thin-film showed the highest conductivity 0.052 Scm-1 at 750℃, the activation energy and electrical band gap calculated from the Arrhenius plot are 0.25 eV and 0.5 eV for the sample sintered at 750oC, respectively. EIS spectra thin-film sintered at 750℃ and 150℃ showed semicircle, which confirms the ionic behavior of the CDC electrolyte thin film. The ohmic resistance also decreased with an increase in the sintering temperature. These results revealed that the thin film shows high ionic conductivity at intermediate temperatures. Which makes it useful for SOFC application.Item Fabrication of Electronic Devices Based on Near Percolation Nanotube Networks(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) Muhammad Tayyab Idrees; CIIT/SP20-RPH-045/LHR; Dr. Abdul Sattar; LHR TP 7694Electronic gadgets that are efficient, compact, light, and cost-effective are in high demand. The fundamental objective of the researchers is to improve the performance of FETs, which are the building blocks of microelectronics. However, the trade-off between mobility and ION/IOFF remains a problem in today's FETs, lowering their performance. The Problems such as the instability of gate dielectric to withstand high threshold voltage in currently used CNTFETs are still unresolved. Also, single CNT based transistors are hard to realize for commercial used due to complexity of the fabrication method. To overcome these problems, firstly, self-assembled Monolayers (SAMs) can be used as a gate dielectric. Secondly to achieve single path CNT active region, lowest possible area coverage of carbon nanotubes much closer to percolation nanotube networks can be used. To overcome this, SWCNTs were used as an active region, and Self Assembled Monolayer (SAM) was used as a gate dielectric. Three different SAMs of different dielectric constants (Octanedithiol (ODT), Dodecanethiol (DDT), Cyclohexanethiol (CHT)) were employed as a gate dielectric in SWCNT-FET. Two different concentrations of SWCNTs were used. SAMs were grown by immersion method while SWCNTs were deposited by the drop-casting method. After the preparation of SWCNT-FET, various analyses were performed using different characterization tools. Electrical measurements were done by Keithley source meter. It was observed that CNTFETs with low concentrations had ten times better properties as compared to high concentration ones. Among SAMs, DDT with low concentration showed an optimum balance between ION/IOFF ratio and mobility. The effective deposition of SWCNTs and SAMs in fabricated devices was confirmed by Raman and FTIR spectroscopy. When CNTFETs were analyzed with SAMs as the only gate dielectric, they performed exceptionally well. Using pure semiconducting CNTs as a channel and passivating the channel surface with SAMs to prevent oxidation and contamination from the environment can boost the device's performance even further.Item Fabrication of Green Template Based Flexible Electrodes for Hybrid Supercapacitors(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) Asifa Iqbal; CIIT/FA20-RPH-030/LHR; LHR TP 7988; Dr. Ishrat SultanaFor rapid charging transfer and ion transport, multichannel-porous carbon generated from wood can act as a conductive substrate, supporting the high-theory capacitance of pseudocapacitive materials. High-performance supercapacitor electrode materials for NiCo2S4 nanosheets that are hierarchically porous and anchored on the surface of carbonized wood were proposed. The NiCo2S4 nanosheet accumulation was successfully reduced, and the hybrid wood-derived porous carbon-NiCo2S4 nanosheet material (NCS-CW) electrode displayed an 821 F g-1 specific capacity. We believe NCS-CW will be used as an electrode material that holds a lot of potential for energy storage devices because of its excellent electrochemical performance.Item Fabrication and synthesis of Graphene Based Material through Microwave Assisted Method(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) Ihsan Abbas; SP19-RPH -013; Dr. Ishrat Sultana; LHR TP 7235Graphene nanoparticles have been used at industrial level, coating and drug delivery. Due to quick response time it is used for solar panels. Presently, energy dearth around the globe arises as a paramount subject to be solved. The rapid demand of energy consumption leads the research direction towards development of highly functional energy devices along with ease of utility. Also the choice of high efficiency materials becomes a crucial counterpart analogue to other factors of device fabrication in energy applications. Modern industries are striving to achieve highly effective, in this study, Graphene sheets were prepared by microwave assisted method with variation in stirring time. The prepared material was characterized by XRD, SEM, Raman and CV.Item Fabrication and synthesis of Graphene Based Material through Microwave Assisted Method(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) IHSAN ABBAS; CIIT/ SP19-RPH-013/LHR; Dr. Ishrat Sultana; LHR TP 7235Graphene nanoparticles have been used at industrial level, coating and drug delivery. Due to quick response time it is used for solar panels. Presently, energy dearth around the globe arises as a paramount subject to be solved. The rapid demand of energy consumption leads the research direction towards development of highly functional energy devices along with ease of utility. Also the choice of high efficiency materials becomes a crucial counterpart analogue to other factors of device fabrication in energy applications. Modern industries are striving to achieve highly effective, in this study, Graphene sheets were prepared by microwave assisted method with variation in stirring time. The prepared material was characterized by XRD, SEM, Raman and CV.Item Investigation and Fabrication of Triboelectric base Nanogenerators for Energy Harvesting Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Muhammad Bilal; CIIT/FA23-RPH-026/LHR; Dr. Amna Mir; LHR TP 9855The increased need for renewable and sustainable energy sources has led to the idea of the Triboelectric Nanogenerators (TENGs), which are considered one of the promising sources of energy that can be converted into electricity at low frequencies. This article reports the design synthesis and fabrication of a compact, high-performing TENG using a composite high-surface-area polyacrylonitrile (PAN) nanofiber with zeolitic imidazolate framework-8 (ZIF-8), a metal-organic framework (MOF) that exhibits structural discretion. The production of ZIF-8 was based on a solvothermal approach, utilizing zinc nitrate and 2-methylimidazole in methanol. The output of PAN nanofibers was achieved through the electrospinning process. A vertical contact- separation mode TENG was developed using the PAN@ZIF-8 composite as a tribo- positive layer and polyethylene terephthalate (PET & Teflon) as the tribo-negative layer. XRD, SEM, FTIR, Raman spectroscopy, UV-Vis, and IV were conducted to characterize the materials. The crystallinity of ZIF-8 was established through the XRD, whereas Raman and FTIR spectra ratified the Zn-N bonding and the integrity of the functional groups. UV-Visible analysis gave a broad optical bandgap of 5.04 eV. The TENG-fabricated device produced a periodically alternating current in response to mechanical stimulation, making it suitable for energy harvesting. The outcomes suggest the potential use of MOF-polymer composites in enhancing the triboelectric capabilities of the material and its applications in wearable electronic systems, self- powered sensors, and IoT devices.Item Fabrication and Characterization of Pani/NiAgCoO3,/Go Nanocomposites for Supercapacitors(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Iqra Akram; CUI/FA23-RPH-021/LHR; Dr. Muhmmad Hammad Aziz; LHR TP 9852Research on high-performance supercapacitors has increased significantly due to the growing demand for dependable, sustainable, and efficient energy storage solutions. In this work, a novel ternary nanocomposite of graphene oxide (GO), polyaniline (PANI), and nickel–silver–cobalt oxide (NiAgCoO₃) was synthesized and built for electrochemical supercapacitors. A synergistic combination of metal oxides with carbon-based materials and conductive polymers is meant to enhance electrical conductivity, cycle stability, and specific capacitance. The NiAgCoO₃ nanoparticles were made using [coprecipitation method]. The NiAgCoO₃/PANI/GO nanocomposite was then created by in-situ polymerization of PANI and mixing with GO. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used to analyze the material's structural, morphological, and electrochemical properties. The composite electrode demonstrated exceptional energy and power density, a high specific capacitance of [insert value] F/g, and exceptional cycling stability, retaining over [insert]% of its energy after [insert] cycles. These results confirm the viability of the NiAgCoO₃/PANI/GO hybrid structure as a possible electrode candidate for next-generation supercapacitors.