Browse
Recent Submissions
Item High surface area metal-organic framework (MOFS) derived mesoporous carbon as an electrode for supercapacitors(UMT, Lahore, 2022) NAIMAT ULLAHThis study aims to develop nanostructured materials based on metal-organic frameworks (MOFs) with high porosity that can be utilized as efficient supercapacitor materials. The materials, Zinc-Nickel-Cobalt ZIF-67 derivatives with varying ratios of Zn and Ni, were synthesized through the co-precipitation method. The MOFs are crystalline materials with high porosity and are composed of metal ion chains linked by organic ligands. Electrodes were fabricated using mesoporous carbon and three samples were prepared with different Zn and Ni ratios, including 1:1, 1:2, and 2:1. These samples were then characterized using techniques such as X-Ray diffractometer (XRD), Raman and Fourier Transform Infrared Spectroscopy (FTIR), Galvanostatic charge-discharge (GCD), cyclic voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS), BET. These characterization techniques were used to determine the crystalline structure, bonding structure, and electrochemical behavior of the samples. The results of this study will contribute to the development of advanced materials for supercapacitor applications and could lead to significant improvements in energy storage technology.Item The investigation of electronic, structural and optical properties of full-heusler Na2TlX (X=Bi, Sb) alloys(UMT, Lahore, 2022) Abu Bakar IqbalNa2TlBi and Na2TlSb Heusler alloys are investigated in terms of their structural, electronic, and optical properties with the help of the full potential linearized augmented plane wave method (FP-LAPW) approach within the carcass of density functional theory or Ab-initio calculation. All physical and other properties of Na2TlX (X=Bi, Sb) Heusler Alloys are computed with Modified Becke Johnson (mBJ) potential. Modified Becke Johnson (mBJ) potential is preffered over GGA because it gives results very close to the experimental data. Electronic properties are computed with mBJ and we observed both alloys have semi conducting behavior with direct bandgap. TDOS and PDOS of both alloys are also determined to check the individual distribution and energy distribution of all the state. Many optical properties including Dielectric function, refractive index, optical conductivity, and energy loss are determined. From the calculated optical properties we can nominate our alloys are good candidate for solar cell applications and for photo-voltaic applications as well.Item Two-stream instability in e-p-i plasma with thermal effects(UMT, Lahore, 2022) Ali Hamza AslamWe have investigated the problem of two-stream instability in electron-positron-ion plasmas. It is well known that to destabilize a plasma system, free source of energy is always required. In two-stream instability case, free source of energy is the energetic beam of electrons, which destabilize electron-ion or electron-positron-ion plasma systems. In the beginning, we discuss the growth rate of two streaming instability in an electron-ion plasma in which electrons were considered to be dynamic and beam of electrons was injected with some fixed streaming velocity, whereas the ions were assumed to immobile to just provide the charge neutrality. The maximum growth has been estimated. Then this work was extended for electron-positron0ion plasma case, in which both the electrons and positrons were assume to dynamic and possessing streaming velocity. New dispersion relation was derived and analyzed numerically. Finally, we have extended this work further by taking into account the thermal effects. New dispersion was derived and the normalized dispersion relation was also analyzed numerically.Item Study of structural, electronic, and optical properties of the 𝐊𝐀𝐜𝐓𝐞𝟐 heusler alloy(UMT, Lahore, 2022) Naeem AbbasSpintronics devices, optoelectronics applications, photovoltaic cells and Radiation shielding have emerged as one of the most exciting areas of research in the field of magnetic materials in the recent past. The interest in this topic is two-fold; applied and fundamental. Extensive research has been carried out in this regard using Heusler compounds. In the present work, KAcTe2 Heusler has been studies using Wien2k code to get various physical properties such as optical, electronic, and structural were investigated by using the full potential augmented plane wave (FP-LAPW), method. For optimization, we have considered the generalized gradient approximation (GGA). The KAcTe2 Heusler complex presses press stability in their non-magnetic cubic phase. The calculated band gap of the selected compounds is (0.81) and (1.59) with GGA and potential. Also, the TDOS and PDOS have investigated that express the complete compounds contribution and individual contribution of each element’s atoms in transition. The optical properties were calculated for photovoltaic and optoelectronic devices.Item Investigation of photocatalytic degradation of methyl green dye by utilizing zinc oxide and carbon nanotubes nanocomposite(UMT, Lahore, 2022) Bakhtawar SarfrazThe present work describes a facile route for degradation and de-colorization of methyl green (MG) dye by pure and multiwalled carbon nanotubes (MWCNTs) doped Zinc oxide (ZnO) photocatalysts under visible light. The MWCNTs have been commercially purchased and ZnO photocatalyst has been synthesized by the chemical precipitation route. The XRD diffractogram of ZnO generally indicates its polycrystalline nature with the prominent peak intensity appearing in the (101) direction, whereas the average crystallite size is estimated as 16.503 nm by using the Scherrer’s formula. Similarly, the XRD pattern for MWCNTs exhibits a sharp peak centered at 2θ equal to 26.1° indicating the inter-planar spacing (d(002)) between walls of carbon nanotubes ~ 3.41 Å, The surface morphological analysis has also been conducted by using FESEM, which specifies nanoparticles based surface texture, whereas the MWCNTs have been observed to exhibit relatively seamless (free from beads) and smooth side walls with randomly and densely entangled tubular structures. During the photocatalytic characterization, after 90 minutes illumination of visible light, ~94.97% and ~ 95.31% degradation of MG aqueous solution has been realized for pure and MWCNTs-doped ZnO photocatalyst, respectively. Specifically, the rate of photocatalytic kinetics (K) ~ 0.03761 min-1 (with R2 ~ 0.95686) has been realized for pure, whereas slightly higher k ~ 0.03869 min-1 (with R2 ~ 0.91965) has been achieved for the MWCNTs-doped ZnO nanoparticles, respectively. The improved photodegradation ability of MWCNTs-doped ZnO may be attributed to the superior charge separation efficiency of doped MWCNTs ZnO photocatalyst.Item Rayleigh taylor instability in a multi-ion magnetoplasma(UMT, Lahore, 2022) Haiqa Nadeem DodhyRayleigh Taylor mode of instability is basically known as gravitational instability. Rayleigh -Taylor instability is instability of an interface between the two fluids of different densities, in which the dense fluid is supported by the light fluid. In order to obtained the results of Rayleigh Taylor instability, we often consider the elements of Hydrogen and Oxygen present in the F-region of ionosphere. We use sinusoidal approximation for the linearized set of equations, which gives real as well as imaginary roots. Applying the linearization method to obtain the desired dispersion relation, in the presence of Gravitational acceleration and density gradient should be in the opposite direction. We found that RT-mode would only destabilize when the density gradients and gravitational acceleration are in the opposite direction.Item Study of optical properties of quartz and fabrication of polarizing element(UMT, Lahore, 2022) ALI RAZAQuartz crystal, which is used in the making of polarizing elements, is found naturally in Pakistan in abundant quantity at a cheaper cost. However, in Pakistan, we have been unable to use this crystal of magnificent optical properties in the optics industry as a phase-changing element such as a retarder. In this research work, firstly the optical properties and structure of quartz are discussed. Later, some samples of quartz have been processed to observe that the unpolarized light gets polarized when it passes from the quartz crystal in a specific direction. This change of polarization states happens due to helical structure of quartz crystal.Item Bandgap engineering of CdS thin films through alloying with CdTe by thermal evaporation(UMT, Lahore, 2022) FAYAZ AHMADBand gap of CdS thin film was engineering through alloying with CdTe by thermal evaporation. In this study, a very simple technique was used to tune the band of CdS films for the desired applications. A different mass concentration of CdTe was added in the CdS powered as starting material. To grow the CdS1-x Te x films. At different concentration of CdTe 0%, 10 %, 15% and 20% the band gap of alloyed CdS1-x Te x films are 2.6 eV, 2.1 eV ,1.9 eV and 1.7 eV respectively. XRD analysis showed that all prepared films are polycrystalline. Optical properties showed that transmittance of CdS was decreased by increasing the CdTe content. It was also noticed that band gap of CdS was decreased by increasing the CdTe content in the film. The morphological properties revealed that the prepared films are not smooth. The voids were present in the films which depicts that high evaporation rate by thermal evaporation. EDX analysis showed that the presence of all the constituents which were present in the initial compounds. The content of Te in the film was increased by increasing the CdTe content in the precursor materials. The electrochemical properties of the prepared samples were measured by three electrode chemical cell and the result showed that 15% CdTe doped CdS films showed better photocurrent response compared to other films because of optimum band gap for water splitting.Item Laser induced breakdown spectroscopy of copper(UMT, Lahore, 2022) SHABANA AZIZThe effect of pressure variation of two environmental gases, argon and helium on the copper plasma parameters electron temperature and electron number density (Te and Ne) has been investigated by using the LIBS technique. Nd: YAG laser (1064 nm, 10 ns) with pulsed energy of 200 mJ and laser irradiance of 141.9 GW/cm2 was used as an irradiating source. The pressure range of argon and helium environmental gases varies from 5 Torr to 500 Torr at fixed energy. The Te of copper plasma was evaluated by using Boltzmann’s distribution method and Ne was measured by using the Stark broadening effect. The environmental gases were used for the enhancement of spectral lines and confinement of the copper plasma. The Te was found from 10000 Kelvins to 12500 Kelvins in the argon gas and ranges from 9000 Kelvins to 11500 Kelvins in helium gas. The Ne was measured ranging from 1.1300 × 1018 cm-3 to 1.15900 × 1018 cm-3 for the argon as an ambient environment and the helium as ambient gas ranging from 1.11300 × 1018 cm-3 to 1.13300 × 1018 cm-3. The results revealed that the Te and Ne showed an increasing trend with the increasing ambient pressure and start to decrease with the further increase in the pressure. The nature of gas and pressure variation of environmental gases highly influenced the characteristics of copper plasma.Item Some linear waves in non-uniform magneto-dusty plasma(UMT, Lahore, 2022) Zaryab AbbasOver the last two decades, several theoretical as well as the experimental observations can be seen in the literature on the physics of dusty plasma. Rao and Shukla, were the first to predict Dust-Acoustic (DA) mode. Later, these authors also predicted Dust-Ion-Acoustic (DIA) mode in dust contaminated plasma. The effect of self-gravitation in a non-uniform magnetized plasma has not yet been studied. In this thesis, we have developed and presented a theoretical model for non uniform, magnetized dusty plasma, whose constituents are electrons, ions and negatively charged static dust particles. Our model equations are the continuity and equation motion and the Poisson’s equation. After linearizing these equation and using sinusoidal wave approximation, we obtain the linear dispersion. In this thesis, we first review and derive dispersion relations for the DA and DIA waves. Then, for in-homogeneous magnetized dusty plasma case, we review the Shukla-Varma mode. But, since it is known that in the presence of heavy dust particles carrying charge, the self-gravitational force cannot be neglected. Therefore, we extend the Shukla-Varma mode calculations by incorporating self gravitational effects. We derived new third order dispersion relation. By using ionospheric parameters, the dispersion relation was analyzed and the growth rate was numerically estimated. It is shown that self-gravity destabilizes the Shaula Varma mode and it introduces Jeans frequency term. These results has applications is space plasmas where the dust particles can be observed.Item Natural fiber/nickel oxide (NiO) based paper electrode for energy conversion applications(UMT, Lahore, 2022) MUHAMMAD ABUBAKAR SIKANDARIn this study LC/NiO based paper electrode are employed to enhance the optical and electrochemical modulation in energy conversion application at nano-scale due to its large band gap, chemical stability, electrical conductivity and optical properties. By complexation precipitation method NiO nano particles have been synthesize that are well defined in terms of size and structure. In this era of advancement with the increasing demand of flexible and portable electronics we incorporate flexibility factor in energy conversion devices in the form of lignocelluloses by replacing FTO and ITO glass with LC sheet. In this article we are working on LC/NiO sheets which are formed through Carica Papaya source. XRD revealed that synthesized NiO has cubic structure and 7nm in crystalline size. The morphology, structure and optical properties of these particles are characterized through X-ray diffraction, FTIR, Scanning Electron Microscope, Cyclic Voltammeter and UV-visible spectrometer.Item The study of structural, electronic, optical and thermoelectric properties of Te2AcGa using DFT calculation(UMT, Lahore, 2022) GHULAM GILLANIUsing the first principle calculations, we have examined the structural, electronic, optical, and thermal properties of Te2AcGa Full Heusler alloy. It’s based on the density functional theory and engage the (FPLAPW) full-potential linearized augmented plane wave method. We have apply two approaches generalized-gradient approximation (PBE-GGA) modified Becke Johnson (TB-mBJ). Firstly, we optimized the cubic structure of Te2AcGa to check the stability of the material. The materials thermal stability completely predicts the formation energy calculated here. The electronic band structures of Te2AcGa show the semiconductor behavior with the indirect bandgap of 0.42 eV and 0.97eV calculated with GGA and mBJ potentials, respectively. The calculated density of states (DOS) also confirmed the semiconductor nature of the material. The electron density contour plot describes the compounds ionic and covalent bonding. The optical properties of the compound have investigated in terms of dielectric constant absorption coefficient optical conductance reflectivity, electron energy loss, and refractive index. The thermoelectric properties also calculated by using the Boltz Trap code. The thermoelectric efficiency increases with the rise in temperature as determined by the power factor. Moreover, the calculated figure of merit (ZT) shows maximum value is 0.79 eV with mBJ potentials. A good deal of ZT with high efficiency makes Te2AcGa suitable candidates for thermoelectric application. It is a full of promising candidate for renewable energy devices. These materials are good candidates for thermoelectric power generation applications.Item An insight into the structural, optical, electronic, and thermal properties of Rb3InI6(UMT, Lahore, 2022) RANA MUHAMMAD NOUMANThe Rb3InI6 compound is being studied with the assistance of the Density Functional Theory (DFT) by which we determine its optical, electric, thermal properties and stability as well. Volume optimization is a key point to discuss the stability as well as the crystal structure of the material. These properties are studied by implementing the Full Potential-Linearized Augmented Plane Wave (FP-LAPW) method within the framework of DFT. To demonstrate the structural parameters the generalized gradient approximation (GGA) and Becke-Johnson (mBJ) potentials are being used separately, which authenticates through comparison with accessible experimental data. The specific impact of electronic states is inspected by the means of both total and partial density of states and it projected that the compound is a direct bandgap semiconductor. All of the properties are computationally investigated with the help of the Wien2k package. Our results will provide useful information related to the utilization of these materials in optical, electronic, and energy devices.Item Some fp- shell model effective interactions with special reference to 42ca(UMT, Lahore, 2022) Kaynat RasheedThere are several effective interactions available for various shells. We select four of the 𝑓𝑝-shell effective interactions namely Kutschera, Mccullen, Banerjee and Engeland for calculating the energy levels for 42Ca comparing their effects using Nushell Oxbash code. The calculation have been performed through F7PN, F7 and FP model spaces. The results are compared with the observed data and discussed.Item A comparative study of some realistic FP-shell model wave functions for nuclear energy levels(UMT, Lahore, 2022) Iqra MujtabaThere are many effective interactions available for various shells. We select four of the fp shell interactions namely Kutschera, Brown, Mooy and Mcgrory and obtain wave functions for calculating the energy levels of one of the fp-shell nucleus. The energy levels are calculated in nuclear shell model with four different approaches using the Nushell Oxbash code. The calculations have been done through 𝐹7𝑃𝑁 𝑎𝑛𝑑 𝐹𝑝 model spaces. The calculated excitation energies of 42Ca for states 𝐽 = 0+, 2+, 4+ and 6+ are respectively obtained from Kutschera, Brown, Mooy and Mcgrory interactions. The results are compared with the observed data and discussed.Item Synthesis and characterization of silver nanoparticles conjugated with folate and curcumin for their anti-cancer activity(UMT, Lahore, 2022) ATTIQA SHEHZADINanoparticles are a wide range of small particles having the size of between 1 100 nanometers. Similarly, silver nanoparticles are nanoparticles made of silver having the same size as nanoparticles. They have been widely used in different branches as well as medicine, health maintenance, food, and commercial use, etc. Silver nanoparticles could be harmful to normal cells in the body regulated by different concentrations and the time-spam of exposure. Besides its harmful effects, it is best for wound healing and killing the bacteria that cause infection. In the past, silver was used as a natural antibiotic. In this study, Silver nanoparticles are conjugated with curcumin and folic acid by the glutaraldehyde method having anti cancer properties. Curcumin is an active compound to kill cancer cells and folic acid is an organic form of vitamin-B9 that will create and preserve the new cells from cancer. Silver nanoparticles are interacted by PEG (Polyethylene Glycol) and further conjugated by Folic acid (C19H19N7O6) and Curcumin. Curcumin is attached to the NH2 – ion connecting with PEG and folic acid is attached to the carbonyl group connecting with PEG. Average crystalline sized Silver Nanoparticles are much more beneficial as compared to chemotherapy and many other radio-therapy cells to kill tumor cells.Item Synthesis and characterization of lignocellulose/SnO2 nano-structure based flexible paper electrodes for energy storage and energy conversion applications(UMT, Lahore, 2022) MUHAMMAD ASIM SHAKEELThe hydrothermal synthesis technique has been used to synthesize tin dioxide (SnO2) nanoparticles. LC/SnO2 fibre sheet has been prepared by filtration and solubility mechanisms through using the corn-silk fibre. The structural, morphological, optical, and electrochemical characteristics of the fabricated SnO2 nanoparticles and LC/SnO2 sheet have been analysed by XRD, SEM, FTIR, UV spectrophotometry and CV (Cyclic Voltammetry). XRD spectra of the SnO2 sample signified that the synthesized nanocrystallites belong to tetragonal structure having an average crystallite size of 30.98 nm. The SEM micrographs of LC/SnO2 sheet revealed that the nanocrystallites found to be of globular and irregular shape having granular size of 32 to 39 nm. It also indicated that the surface of LC/SnO2 sheet showed hollow-like structure having spaces and voids. The red-shifted optical bandgaps values of the SnO2 nanocrystals and LC/SnO2 sheet are 4.28 eV and 3.30 eV respectively. The electrochemical properties of the LC/SnO2 fibre-sheet and LC sheet have been analysed in the aqueous 2M electrolytic solution of KOH by using CV technique. The specific capacitances of the fabricated electrodes are found to be 5.17 μF/g and 3.66 μF/g.Item Synthesis and characterization of lignocellulose/zinc stannate (LC/Zn2SnO4) nano structure based paper electrode for energy storage and energy conversion applications(UMT, Lahore, 2022) GHULAM MURSALINHydrothermal synthesis has been utilized to prepare zinc stannate (Zn2SnO4) nanocrystals by NaOH as a mineralizer. The LC-Zn2SnO4 sheet has been fabricated through filtration and solubility by using corn-silk fibre. The structural, morphological, optical, and electrochemical characteristics of the prepared LC- Zn2SnO4 sheet and Zn2SnO4 nanocrystallites have been analysed by XRD, SEM, FTIR, UV spectrophotometry, and CV (Cyclic Voltammetry). X-ray crystallographic spectra of the Zn2SnO4 indicated that the synthesized nanocrystals having cubic structure and average crystallite size of 24.7nm. SEM micrographs of LC- Zn2SnO4 sheet revealing the spherical shape of NP’s and particles having size in the range of 39-47nm. It also showed that the surface of the LC-Zn2SnO4 sheet signified a hollow-type structure possessing holes and valleys. The red-shifted optical bandgaps of the Zn2SnO4 nanoparticles and LC Zn2SnO4 sheet are 3.7 eV and 2.45 eV respectively. The electrochemical nature of the LC-Zn2SnO4 sheet and Zn2SnO4 nanoparticles have been assessed in aquatic 3M electrolytic solution of KOH by using the CV technique.Item Using DFT calculation to investigate structural, electronic, magnetic, and optical properties of AcXO3 (X=Cr, Fe) compounds(UMT, Lahore, 2022) Muhammad Khuram IftikharAcCrO3 and AcFeO3 perovskite oxide compounds are investigated in terms of their structural, electronic, magnetic, and optical properties with the help of the full potential linearized augmented plane wave (FP-LAPW) approach within the carcass of DFT calculation. All physical and other properties of AcXO3 (X=Cr, Fe) perovskite oxide compounds are computed with Modified Becke Johnson (mBJ) potential. Modified Becke Johnson (mBJ) potential is preferred over GGA because it gives results very close to the experimental data. Electronic properties are computed with mBJ and we observed the semiconducting behavior of both compounds in both spin channels with an indirect bandgap. The magnetic properties are calculated to find out the contribution of each element of compounds in the magnetism. Many optical properties including the Dielectric function, refractive index, reflective coefficient, optical conductivity, and energy loss are determined. We can say that our compounds are good for optic and electronic devices in the ultra violet region from the optical properties of both compounds.Item Preparation and characterizations of CdTe/ZnO thin film heterostructures for hydrogen generation via water splitting(UMT, Lahore, 2022) MAMOONA RIFFATSemiconductor photocatalysts have been extensively studied in recent decades to generate hydrogen via water splitting. In order to effectively utilize solar radiations, this thesis investigates the various types of bi-layer CdTe/ZnO heterostructures prepared at different temperatures using physical vapour deposition (PVD) and physical vapour deposition (PVD). The bi-layer of CdTe/ZnO enhanced the visible light absorption and photocatalytic ability. Thin film technology employed an efficient photoelectrochemical sensor to maximize the solar to hydrogen conversion efficiency. Heterostructures have potential applications in the field of optoelectronics, sensor devices, vertical field effect transistor, etc. Therefore, it is crucial to investigate heterostructure semiconductors for photoelectrochemical water splitting since they have a variety of functionalities that can significantly speed up the conversion of solar energy into hydrogen. In this thesis, a physical vapour deposition technique (PVD) was used to deposit a thin film of CdTe on ITO substrates. Furthermore, the bi-layered heterostructure of CdTe/ZnO was prepared in a tube furnace using chemical vapour deposition (CVD) and optimized at various temperatures. The characterization techniques were used to investigate the structure, morphology, and features of the prepared specimens. In this thesis, photoelectrochemical properties were explored with the help of photoelectrochemical cell using photoelectrolysis. The CdTe/ZnO thin film heterostructure prepared at 700oC showed 65-fold better results than pristine CdTe. The photoelectrochemical efficiency of the CdTe/ZnO thin film heterostructures prepared at 600oC, 650oC, and 700oC is 4.5%, 8.46%, and 11.52% respectively.