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Item Optical properties of Yttrium Oxide thin films prepared by SOL-GEL method(UMT, Lahore, 2024) YASIR NADEEMYttrium oxide (Y2O3) thin films have piqued the interest of researchers in recent years due to their numerous useful uses in optoelectronic and solar devices. Using these thin films for both industrial and scientific uses is standard procedure for researchers. In this study, yttrium oxide thin films are prepared using an application oriented sol-gel approach. The range of molar concentration is 0.1M to 0.6M. Structural and optical properties are acquired using an X-ray diffractometer (XRD) and a Variable Angle Spectroscopic Ellipsometer. At all molar concentrations, XRD analysis verifies the development of pure cubic phases in yttrium oxide thin films. As the molar concentration rises, the crystallinity of thin films increases, which results in an increase in the crystallite size value. Optical analysis confirmed that the prepared samples resulted with wide direct band gap, high refractive index and high transparency in the visible near infrared region. High value of transmission (~ 90%) along with direct band gap (~5.83) is observed for 0.6M molar concetration. The yttrium oxide thin films exhibit a band gap energy ranging from 5.76eV to 5.83eV. Furthermore, as the molar concentration increases, optical-constants, n and k of Y2O3 films tend to rise for all concentrations. Results suggest that this could be advantageous for the material's future application as yttrium oxide thin films proved to be promising candidate for optoelectronic devices. In order to maximize the potential of the approach, this work will stimulate further research on the creation of Y2O3 thin films using the spin coating sol-gel technique.Item Design and implementation of a low-cost spin coater for thin film deposition(UMT, Lahore, 2024) SAHA ZAINAB; SYEDA SAMREEN ZAIDIThe design and development of the economical and efficient spin coater is described in this paper. A spin coater deposits a film uniformly on the target material and can be made using information of various disciplines such as Electronics, Mechanics and Physics. The system is developed using a brushless motor along with an Arduino and ESC for accurate speed regulation making it simple and cost effective. An Arduino is used as a microcontroller to coordinate the coating process and communicate with the LED display and ESC. The spin coater has a speed range from 500rpm to 1500rpm, making it easy to develop different film thicknesses, which can be controlled depending on the material used. This spin coater, developed with easily accessible mechanical and electronic components, offers a user-friendly approach for achieving uniform thin films, making it appropriate for widespread use in academic and research settingsItem Synthesis of ternary metal oxides with carbon composite as high-performance electrode materials(UMT, Lahore, 2024) Meishaar HussainThis study involves the synthesis of two samples with the variation of molar concentration of a ternary Zirconium-Nickel-Cobalt ZIF-67 composite (ZrNiCo ZIF 67) using the co-precipitation method. The samples vary in the molar concentration of ZrO (NO3)2, Ni (NO3)2, Co (NO3)2, and BTC (C9H6O6). The composite is generated from MOF. Both of these samples have undergone electrode manufacturing. The features of ternary metal oxides ZIF 67, such as their high surface area, porosity, chemical stability, adjustable qualities, redox activity, and eco-friendliness, have made them a promising material for supercapacitor electrodes. The charge storage capacity of ZrNiCo ZIF-67 is significantly enhanced by its porous polyhedral structure, which contains linked nanoparticles of varying compositions. They are economically, ecologically, and socially significant, and they are fundamental to a strong and sustainable energy future. When evaluating the performance of the electrode, many characterizations are employed, such as X-ray diffraction, and electrochemical methods like cyclic voltammetry (CV), galvanostatic charge and discharge (GCD), and electrochemical impedance spectroscopy (EIS). At a current density of 1 A/g, the ZrNiCo ZIF-67 (2:1) electrode material outperforms the other ZrNiCo ZIF-67 (1:1) materials with a specific capacitance of 247 F/g. As electrode materials for supercapacitor applications, these studies give a straightforward and effective way to generate nanocomposites ZrNiCo ZIF-67 (2:1) with enhanced electrochemical properties.Item Effect of concentration variation on zirconium nickel cobalt metal organic framework-based electrode material for supercapacitor applications(UMT, Lahore, 2024) Taimoor AkbarIn this research, two samples of a ZrNiCo ZIF-67 with the change in molar concentration of metal to linker (1:1 and 1:2) were synthesized via the co-precipitation method. Then electrode fabrication was done. An attractive candidate for supercapacitor electrodes, ternary metal oxides ZIF 67 exhibit a number of desirable properties, including a large surface area, porosity, chemical stability, tailor ability, redox activity, and low environmental impact. The porous polyhedral structure of ZrNiCo ZIF-67, which incorporates connected nanoparticles of varied compositions, greatly enhances the charge storage capacity. They are essential to a robust and sustainable energy future, and they have social, ecological, and economic significance. Electrochemical methods such as cyclic voltammetry (CV), galvanostatic charge and discharge (GCD), and electrochemical impedance spectroscopy (EIS) are among the various characterizations used to assess the electrode's performance. Other approaches include X-ray diffraction to study the crystal structure. With a specific capacitance of 232 F/g at a current density of 1 A/g, the ZrNiCo ZIF-67 (1:2) electrode material performs better than the other ZrNiCo ZIF-67 (1:1) materials. In order to create nanocomposites ZrNiCo ZIF-67 (1:2) with improved electrochemical characteristics, this research provide an easy and practical method. These materials can then be used as electrodes in supercapacitors for high specific capacitance.Item Laser surface structuring of stainless-steel alloy for biomedical implants application(UMT, Lahore, 2024) MUHAMMAD SAJAWALThis work aims to roughen the surface and enlarge the surface area of the sample material, stainless steel alloy 304S, through laser surface structuring (LSS) for biomedical applications. LSS is used to alter the surface of sample material by developing various patterns, textures, and microstructures on the surface. In this study, the surface treatment of stainless steel alloy 304S was performed using 1064nm ND:YAG laser. After LSS, field emission electron microscopy (FESEM) was used to determine the surface morphology. FESEM is an advanced technique employed to obtain the microstructure of the material. The FESEM results showed pits on the stainless steel alloy 304S. Pits greatly increase biomedical implants' surface area, biocompatibility, usefulness, and performance. A wettability test was conducted to check the hydrophilicity or hydrophobicity of the laser-treated sample by using the sessile drop method. Wettability is measured by angle measurement. If the angle is greater than 90 degrees, the surface is hydrophobic, if the angle is less than 90 degrees, the surface is hydrophilic. Wettability determines how well the material will be accepted by the human body. The sample's contact angle was 78 degrees, according to the results. Because the sample's contact angle is below 90 degrees, it is hydrophilic and wettable. Therefore, the treated sample is suitable for bioimplants.Item Enhancement of surface area and wettability properties of titanium by femtosecond laser induced periodic surface structuring(UMT, Lahore, 2024) MUHAMMAD BIN AKRAMLaser Surface Structuring (LSS) is a well-known technique used to alter the topological and tribological properties of solids, usually to make them more suitable for certain applications. Our aim was to use it on a titanium sample to make it more bio-compatible. We wanted to make our sample more osseointegral, so that it would show better results when placed inside a human body. Research shows that enhancing a substance’s wettability to make it more hydrophilic can produce improve desired qualities such as protein assimilation and cell adhesion. We had one sample of medical grade titanium (Ti6Al4V), which we used a Ti:Sapphire femtosecond laser on to alter its surface properties and wettability. Afterwards, it was observed using FESEM and the sessile drop method, which revealed enhancements in surface roughness and wettability.Item Polytropic winds(UMT, Lahore, 2024) SAYOON SARWARAll stars emit plasma outflows in every stage of their lives. The energy and velocity of these outflows change as a star shifts from accretion phase into a developed main-sequence star. In this thesis we discuss the effect of polytropic index on the energy of the stellar outflows. We first discuss the types of stellar outflows observed,their composition and the means by which they are ejected from the surface of the star. We also discuss the types of models that are used in mapping the outflows of stars in the literature review section. Further, we explain the hydrodyanmical model and present the governing equations for the case of one-fluid model. Lastly, we show results of using the polytropic model on plotting the velocity profile of the stellar wind and show that polytropic index has a great effect on the energy on the wind alongside which we also discuss the applications of this study.