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Item Synthesis and characterization of flexible AL-doped SnO2 based paper electrode for perovskite solar cell application(UMT, Lahore, 2022) MUHAMMAD USMAN BUTTFirstly, Perovskite solar cells (PSCs) were disclosed merely in 2012 but their tremendously fast development has reached an efficiency of confirmed 22% presently. PSCs are low-cost and easy to develop than Silicon based solar cells and they can respond to many wavelengths of electromagnetic spectrum which helps them transform more light into electricity. The performance and stability of PSCs are mainly reliant on the Electron transport layer (ETL) material. Lignocellulose (LC) is an abundant, environmentally friendly and a biodegradable fiber. In this research work, LC fiber is used as a substrate instead of glass substrate due to its flexibility and better sustainability. For Electron transport layer materials in PSCs, several semiconductors can be utilized. In this research article, SnO2 is used as an Electron transport layer material because of its low temperature fabrication and wider bandgap. Overall, SnO2 exhibits great optical transparency, chemical stability, conductivity and electron mobility which display its good photovoltaic properties. Aluminium was added into SnO2 as a dopant for the thin film enhancement and for the improved Power conversion efficiency (PCE). Al-doped SnO2 proposes a fine surface coverage of thin films and enhances the conductivity of ETLs which results in the better performance of the PSCs. Different Characterization techniques such as X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Ultraviolet-Visible Spectroscopy (UV-Vis) were used to characterize the synthesized material. The results display that the conductivity of Al-SnO2 increased as the bandgap reduced due to Al-doping and inclusion of LC fiber. Therefore Al-doped SnO2 constituting ETL prepared at low temperature display an enhanced charge transport than that of undoped-SnO2. Hence, Al-doped SnO2 is a favorable contender for ETLs used in PSCs which gives high Power conversion efficiency and stabilization.Item Synthesis of silver nano particles by co-precipitation method and its characterizations(UMT, Lahore, 2022) ANWAAR UL HASSANSilver Nanoparticles have been synthesized by using co-precipitation method. The synthesized particles monitored by UV-Visible spectroscopy, XRD and Zeta Potential analysis. The UV-Visible spectroscopy results shows absorption peaks at 419nm that confirm SPR band of silver and the XRD results showed Face centered cubic structure having 35.1nm particle diameter and Zeta Potential value -26.2mV showed good stability that confirms the Antibacterial activity of silver.Item Synthesis and characterization of flexible copper doped nickel oxide-based paper electrode for perovskite solar cells applications(UMT, Lahore, 2022) MUHAMMAD ANAS TOHEEDPerovskite-based solar cells are involved in solar cell production as they enhance power conversion efficiency. The stability and performance of cells are mainly reliant on the materials used as hole transportation materials. One of the vital constituents of the perovskite solar cells is hole transporting layer. The supreme hole transporting material is the one that retains high hole mobility, durable air and mechanical stability and should have energy levels that are a suitable match with the perovskite layer. Lignocellulose (LC) fiber is reflected as a very abundant, eco-friendly, lightweight natural fiber and a biocompatible polymer. In this work Lignocellulose (LC) fiber is used as a substrate. As hole transporting materials (ETM) for perovskite solar cells, many kinds of semiconductor materials can be employed. In this research work, NiO is used as hole transporting material (HTM) due to its superior electrical properties, long-term mechanical and air stability, high hole mobility, and high conductivity. To enhance the properties of NiO thin films and also increase the power conversion efficiency of perovskite solar cells, Cu was added into it as a dopant. Cu-doped NiO (Cu:NiO) has a high conductivity compared to pure NiO. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Ultraviolet-Visible Spectroscopy (UV-Vis), were carried out to characterize the synthesized material. It was indicated that Cu:NiO has better efficiency as a pure NiO when used as hole transporting material (HTM) in the Perovskite solar cells (PSC).Item Qualitative and quantitative analysis of Sulphur element in Pakistani rice by calibration free laser induced breakdown spectroscopy (LIBS)(UMT, Lahore, 2022) ZEESHAN YOUNASLaser induced breakdown spectroscopy is being used as rapid, non-destructive in-situ technique equally reliable for compositional analysis for metals and non-metals. In this work a 1064nm Nd:YAG laser was used for the calibration free LIBS. Three samples of the rice were used for the qualitative and quantitative analysis for Sulphur element. Sample-1 was analysed under vacuum and other were determined in the presence of Ar gas filled in the chamber for the confinement of plasma signature. After the identification of Sulphur peaked lines according to NIST (National Institute of Science and Technology) was used for data according to our desired conditions. Plasma properties (Temperature and Density) were calculated and temperature was almost same for all the samples but the density of electrons vary for sample to sample plus for ionized and neutral atoms of Sulphur. Our main concern was to check the permissible value of Sulphur in rice, which then quantified and surprisingly all were above the acceptable value (2ppm) in food. LIBS with a coupled with a suitable medical and agricultural analysing techniques would be more beneficial for the compositional analysis and recommendations in the field of health and agriculture.Item Influence of repetition rate on the growth of MgO thin film by pulsed laser deposition technique(UMT, Lahore, 2022) TAHIR SAJJAD BUTTThe thin films of Magnesium Oxide (MgO) were fabricated onto a substrate of Si (100) by pulsed laser deposition (PLD) of the MgO target with varied repetition rates of 2, 3, 4, and 5 kHz respectively. Nd: YAG laser with a fundamental wavelength of 1064 nm was applied as an energy source with pulse energy of 100 mJ and vacuum as the background environment. The X ray Diffraction (XRD) revealed that the preferred orientation of thin films would be altered from (220) to (311) by increasing thickness. Crystallite sizes were decreased from 65 to 15 nm with an increasing thickness of 307 to 960 nm. It was observed that grain size and film thickness increase with an increase in repetition rate (number of laser shots) while the crystallite size decreases as the repetition rate increases. The surface structure and topology of thin films were analyzed by applying a Scanning Electron Microscope (SEM) which demonstrated that there was no presence of cracks and the film was highly smooth. Such films were suitable as buffer layers for the growing high-quality ferroelectric and superconducting over layers