Department of Physics
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Item Mxene and Graphene based Nano Composites for Energy Storage Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2022) Tariq Ali; CIIT/SP21-RPH-024/LHR; Dr. Muhammad Ashfaq Ahmad; LHR TP 8168With the rapid growth of the human population the energy crisis is also growing in the world. To address this problem, it is essential to design and fabricate energy conversion.and storage devices. Among all available energy storage devices, supercapacitors (SCs) have attracted more attention from the current research community because of their unique features. MXene is regarded as one promising candidate for supercapacitors due to its high electrical conductivity and volumetric capacitance. MXene is a newly developed two-dimensional (2D) material. It is a very suitable substrate for fabrication due to its high electrical conductivity and large specific surface area. The two-dimensional MXene (Ti3C2Tx) sheets stacked quickly, reducing their specific surface area and charge/mass transport properties. However reduced graphene oxide presumed as significant part to improve the electrochemical behaviour. Graphene combined with MXene resolve the restacking problem and promote rapid ion diffusion in electrode materials. In this project, the Mxene/rGO composite will be synthesized through simple and facile hydrothermal treatment. The manufactured nanocomposite will be used as efficient electrode material for energy storage devices such as supercapacitor. Also, the various samples of graphene oxide were prepared using different nitrates as precursors with varying recipes via Modified hummers method and Improved Hummers method. The proposed materials are GtO, XGO, Na-GO, Mn- GO, Cu-GO, Ni-GO, Zn-GO, GO, 5M-rGO, 10M-rGO and M-GO film. The prepared samples were characterized by different characterization techniques such as Raman, PL, FTIR, UV-VIS and Electrochemical Impedance Spectroscopy (EIS). Raman spectroscopy can be used to examine the chemical components of materials by detecting vibrational, rotational, and other modes in a molecular system. The Raman spectra shows the D, G and 2D bands attributing the defects states and successful oxidation of GO. The broad and asymmetric emission peaks ranging between 500-900nm were observed by photoluminescence spectra. The remarkable sharp emission peak at 600, 599 nm (visible range) for Cu-GO, Ni-GO and Zn-GO is caused by the presence of CO, C=O, and O=C-OH functionalized groups on the GO. The highest PL intensity is occurred at 717, 795 and 721 nm for GO, 5M-rGO and 10M-rGO indicating the red shift for all samples due to some extrinsic defects. FTIR technique is employed to study the chemical composition and its bonding. All the samples accommodate numerous functional groups like epoxy, carbonyl, hydroxyl, and carboxyl. The straight line in lower frequency portion indicates the capacitive behaviour of the electrode material. The EIS analysis investigated the charge transfer property and capacitive nature of the synthesised electrode material. From Nyquist plot of GO, Mxene 5M-rGO and 10M-rGO the slope of the curve decreases in the low frequency region demonstrating the fast ion diffusion/transportation properties. The observed band gap is 2.2eV, 1.53.9eV 2.19eV and 1.6- 3.43eV for GO, Mxene, 5M-rGO and 10M-rGO. It is indicated that all the samples show good absorption in the visible range (300-800nm). The main peak at round about at 230 nm represents the π-π* transitions of C=C bond. The shoulder peaks at round 330 nm stands for n-π* transitions of C=O bonds. Thus, the fabricated Mxene and graphene- based nanocomposite offer to be a promising material in energy devices with high energy. The cyclic voltammogram of our synthesized electrode material was compared with individual materials worked as electrodes at same potential window and scan rates and in same electrolyte as mentioned above. The shapes of CV curves for GO and Mxene were found to be approximately rectangular and symmetric, even at high scan rates, demonstrating excellent capacitive behaviour and rate performance. The CV curve for 5M-rGO can be observed to be well almost rectangular, revealing that it can serve as best electrochemical double layer capacitor (EDLC) electrodes.Item Fabrication and Characterization of Zinc Sulfide and Natural Fibers Based Flexible Composite for Energy Storage Application(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2021) Muhammad Ansar; CIIT/SP19-RPH-018/LHR; Dr. Muhammad Aamir Razaq; LHR TP 7255Metal Sulfides are commonly employed as an electrode for energy storage applications due to versatile characteristics of high-power density and cycling stability in comparison of metal oxides. Among metal sulfides, zinc sulfide is promising due to facile synthesis and wide potential window. However, zinc sulfide based electrodes are limited to employ in modern bendable/flexible energy storage devices due to inherited rigid structure. Lignocelluloses (LC) fibers known as natural fibers can incorporate flexible matrix for zinc sulfide nanostructure to develop flexible and environmentally safe paper electrode for energy storage applications. Presented research shows successful fabrication of zinc sulfide nanostructure via facile microwave assisted method and developed bendable ZnS/LC composite paper sheets. Furthermore, fabricated composition sheet is successfully prepared and analyzed by X-ray diffraction (XRD, Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, Cyclic voltammetry (CV) and Galvanostatic charge discharge (GCD) characterizations for energy storage applications.Item Fabrication and Characterization of Tin Oxide Based Flexible Composites for Energy Storage Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2017) NAEEM MUNIR; CIIT/FA15-RPH-030/LHR; Dr.M Aamir Razaq; LHR TP 6986Tin Oxide (SnO2) is excessively used for energy storage applications due to wide potential, transparency and thermal stability. Several methods are reported for fabrication of SnO2 nano structures e.g. electro spinning, chemical vapor deposition process, self assembly, homogeneous precipitation method, thermal decomposition and hydrothermal method. Hydrothermal method is advantageous due to low cost, template free, environment friendly and low temperature. In this study, SnO2 is fabricated via hydrothermal method and furthermore composites with CuO, ZnO and lignocelluloses fiber are synthesized for development of electrochemically efficient and flexible paper electrodes for energy storage. X-Ray diffraction, Scanning Electron Microscopy (SEM), FTIR and Cyclic Voltammetry measurements of fabricated composites were employed to characterize the morphology, structural and electrochemical characteristics. SEM reveals the nano-petal and nanorods morphology of SnO2 and CuO, respectively. XRD measurements confirm the fabrication of SnO2, SnO2/CuO and ZnSnO3 by JCD cards (41-1445), (48-1548) and (34-1451) respectively. Cyclic Voltammetry confirm the electrochemical kinetics of fabricated composites which are highly feasible for super capacitors and batteries.Item Fabrication and Characterization of High Surface Area/Nanostructured Metal Based Composites for Energy Storage Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) Muhammad Ahmar Chohan; CIIT/SP18-RPH-006 /LHR; Dr. Ishrat Sultana; LHR TP 6070Novelty in energy storage and energy conversion devices have been received subjected of great interest as an alternative energy source in nanoscience and nanotechnology. Nanostructure materials have a lot of potential in energy storages application due to their dimensions which plays a vital rule in defining the properties of nonmaterial. We have many materials for energy storage applications, amongst many of the materials manganese dioxide (MnO2) is very suitable medium for supercapacitors and electrodes. In this thesis we have fabricated MnO2 nanostructure as an electrode material for energy storage and energy conversion devices by employed Microwave Assisted Method with freedom of template fee synthesis. Amongst many of the metal oxides, MnO2 exhibit a lot of interesting characteristics, for instance inexpensive, eco-friendly, and a high specific capacitance (1370 F g−1), propose it as the most favorable electrode medium for supercapacitors. Presented thesis is an attempt to enhance the specific capacitance and high surface area of MnO2 composites for their potential applications as energy storage devices.Item Preparation and Characterization of Solid-State Electrolyte Material for Energy Storage Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2019) Muhammad Shahzad; CIIT/FA17-RPH-012/LHR; Dr. Junaid Amjad; LHR TP 5713Seven Boro-phosphate samples with composition (70 - x) B2O3 – 30 Na2O3 – xP2O5 where x=0.5%, 1%, 1.5%, 2% and 3, 5, 10 mole% and 0.02 g Er2O3 in extra were prepared using melt quenching method. From the results of X-ray Diffraction (XRD), it was confirmed that the structure of the samples was amorphous. Amorphous materials have open structure, so they can facilitate in the conduction. Samples were characterized by UV-Visible near Infrared (UV-Vis-NIR) spectroscopy. The spectroscopy was performed with wavelength ranging from 400 nm to 1600 nm to obtain the absorption peaks of the samples. Five absorption peaks were observed because of the transition from the ground state 4I15/2 to the different excited states. From the results, direct and indirect energy band gaps were calculated. Direct energy band gaps were in the range 3.59 eV - 4.18 eV. Indirect band gaps were in the range 2.92 eV - 3.95 eV. Refractive index was also calculated which was in the range 2.19 - 2.42. Photoluminescence was performed between 200 nm to 800 nm to observe the emission peaks of the samples. Two broad peaks were observed centred at 540 nm to 565 nm. These peaks were due to the transition from 2H11/2 → 4S3/2 and 4S3/2 → 4I15/2 respectively. Then Raman spectroscopy was performed on the samples between 200 cm-1 to 1600 cm-1. Under an excitation wavelength of 488 nm, characteristic Raman peaks of borate and phosphate were observed. Shifts and appearance of new bands were due to the replacement of borate with phosphate contents.Item Electrodeposition of Metals on Paper Based Electrodes for Energy Storage Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2019) MAHAM SANA; CIIT/FA17-RPH-033/LHR; Dr. Ishrat sultana; LHR TP 5724This research aspires to have an unconventional and alternative source for flexible and bendable energy storage devices, which has proved themselves very useful to meet the demand of today’s energy crises. It is very interesting to use natural self-growing plant’s lignocelluloses, which are very abundant on earth and convert them in the form of paper-based electrodes. In this research, Lignocelluloses were extracted from natural source Monochoria vaginalis (MV). Different samples were prepared for electrodes of energy storage applications like LC/PbO2/Au LC/PbO2/Ag, LC/PbO2/Ni by using single layer electrodeposition technique. Before using these samples as an electrode material for energy storage devices we characterized the samples for Electrodeposition, Scanning Electron Microscope, Cyclic Voltammetry and FTIR spectroscopy. Electrodeposition of Metallic layers are deposited on LC/PbO2 sheet by using three electrode setups. The SEM analysis displayed the fine fibril structure interlocked with each other displaying high mechanical properties with significant electrodeposited layers of Au, Ni and Ag. In these samples the nanoparticles of gold, silver and nickel are clearly visible with uniform electrodeposition. FTIR conforms the electrodeposition of gold, silver and nickel nanoparticles on LC/PbO2 sheet. CV is carried out for the LC/PbO2/Au, LC/PbO2/Ag and LC/PbO2/Ni samples displaying the amount of current increasing with increasing deposition timeItem Synthesis and Characterization of Nano Composites for Lithium Ion Batteries(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2019) Najam Ul Haq; CIIT/FA17-RPH-001/LHR; Dr Ashfaq Ahmad; LHR TP 5710Paper electrodes are categorized as an emerging technology for flexible and environment friendly energy storage and energy conversion devices including, batteries, supercapacitors and solar cells. But the use of paper electrodes is somehow limited because of their low conductivity, due to the presence of insulating matrix in it. But this issue can be resolved by depositing a metallic layer on paper electrode to enhance the conductive properties of paper electrodes. This study presents the deposition of metals by three different techniques i.e. Electrodeposition, Sputtering and Dip coating. Electrodeposition is carried out by depositing ions of metals on substrates. Sputtering is done in the presence of vacuum while in dip coating a substrate is simply submerged into solution of metals. Fibers from Monochorea Vaginalis plant were taken and then dried, which were then treated in bleaching solution to make flexible and smooth sheet. Then, these sheets were further used to make LC/TiO2 composite sheet with ratio of 1:5. Then these sheets used for depositing gold and silver on it by using three different approaches i.e. Electrodeposition, Sputtering and Dip Coating for different time intervals. Electrodeposition and Dip coating was done for 3000, 6000, 9000 secs while sputtering was done for 100 and 200 sec. By depositing gold and silver on LC/TiO2 composite sheets, we obtain paper electrodes as depositing a metallic layer enhance the electronic conductivity of sheet. Then, these samples are characterized using different techniques SEM , FTIR, CV and Specific capacitance. Structural analysis using SEM confirm the deposition of metallic layer . While FTIR also confirm the presence of gold and silver in it. CV and Specific capacitance show the enhancement of conductivity after deposition of metals on LC/TiO2.Item Extraction of Carbon Based Biochar fromWasted Biomass for Energy Storage Application(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Aftab Javid; CIIT/FA23-RPH-003/LHR; Dr. Muhammad Aamir Razaq; LHT TP 9838The growing need for powerful eco-friendly energy storage has determined research into better electrode materials for supercapacitors. Supercapacitors famous for their fast charge and discharge cycles and high-power output, but their energy storage capacity remains relatively low, when relying on Bismuth Sulfide (Bi₂S₃). To solve this, we use Biochar, a carbon-rich material that can both store more electrons and also facilitates fast electron transport. In this study, we created a binder-free electrode by growing Bi₂S₃ directly onto Biochar made from Amal Tass pods biomass waste, using a fast microwave-assisted process. First, we turned the Amal Tass pods into conductive biochar through drying, grinding, and a simple hydrothermal step. Then mixed this biochar into water with Bi(NO₃)₃·5H₂O and thiourea, and exposed the mixture to microwave energy and a uniform Bi₂S₃–Biochar composite formed, no binders or extra additives needed. This composite delivers a high energy density, making it a strong candidate to replace batteries. Raman spectroscopy confirmed that Bi₂S₃ adopted its orthorhombic crystal structure within the carbon matrix, and it also showed the characteristic D- and G-bands of biochar at 1391 and 1595 cm⁻¹. When we tested the composite in 2 M KOH, cyclic voltammetry revealed clear redox peaks whose areas raised with scan rate, indicating strong pseudocapacitive behavior. Electrochemical impedance spectroscopy showed low charge-transfer resistance, which means ions and electrons move through the material with ease. Together, these results demonstrate that our quick, green microwave method produces Bi₂S₃–Biochar electrodes that combine high power with improved energy storage an encouraging step toward the next generation of sustainable pseudocapacitors.Item Facile Synthesis of MgWO 𝟑 Incorporated With N Doped Graphene Oxide for Energy Storage Applications(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Ali Haider; CUI/FA23-RPH-004/LHR; Dr. M Hammad Aziz; LHR TP 9839Uses of Energy Storage and Their Significance Electrical grid stabilization, renewable energy integration, time shifting and microgrids, backup power, electric car charging, and energy consumption optimization in commercial and industrial settings are just a few of the uses for energy storage systems. A relatively new field of technology, large-scale renewable energy storage has expanded quickly in tandem with the growing demand for more energy from sources worldwide. Renewable energy's main disadvantages are its reliance on the weather and its incapacity to store and transmit power when needed. New long-term and short-term storage concepts are constantly being developed to improve energy conversion efficiency, even if there are presently a number of commercially viable kinds of energy storage. Demanding methods include chemical storage through electrolytic reactions and electrical energy storage.Item Synthesis and Characterization of Magnesium- Based Metal Organic Framework (MOFs) for Energy Storage Application(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2025) Shahzad Safdar; CIIT/FA23-RPH-039/LHR; Dr. Muhammad Aamir Razaq; LHR TP 9865This research presents the sustainable synthesis of magnesium-based metal-organic framework (Mg-MOFs) composites integrated with lignocelluloses (LC) fibers derived from corn husk via a hydrothermal method route using Mg(NO₃)₂·6H₂O and H₃BTC as precursors. Magnesium was utilized because it is abundant, environmentally friendly, less reactive, cost-efficient, and an electrochemically compatible material. The resulting Mg-MOFs/LC composite harnesses the synergistic benefits of both components—magnesium offers lightweight characteristics, moderate electrical conductivity, and structural integrity, while lignocelluloses fibers provide biodegradability, flexibility, and environmental safety. Structural and optical characterizations confirmed successful composite formation. UV-Visible spectroscopy revealed enhanced light absorption with notable π→π* transitions and a red-shifted absorption edge (2.73 eV), showing strong interfacial electronic coupling. Raman spectroscopy found key vibrational modes, including Mg–O bonds and aromatic linker structures, alongside preserved organic functionalities. Electrochemical assessments showed that cyclic voltammetry shown pronounced redox activity with a high area under the curve. Although the specific capacitance of Mg-MOFs is 122 F/g but a reduction in specific capacitance was seen with LC incorporation, galvanostatic charge- discharge measurements proved extended discharge times and strong redox behavior, highlighting effective charge storage and diffusion. The EIS of composite show the less resistance as compared to Mg-MOFs. With its eco-friendly fabrication, mechanical resilience, and promising energy storage performance, the Mg-MOFs/LC composite appears as a practical material for next-generation flexible and biodegradable supercapacitor applications.