2023

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Anti-diabetic activity of metal oxide nanoparticles on alloxan induced diabetic mice
(UMT, Lhr, 2023) GOHER AYUB
Diabetes is a metabolic disorder considered either due to the resistance of insulin or lack of insulin production and hyperglycemic effects. Metallic nanoparticles have been reported as therapeutic agent against many metabolic diseases. Our study was designed to analyze the anti-diabetic activity of synthesized metal oxide nanoparticles; Titanium oxide (TiO2), and Cobalt oxide (Co3O4) for drug delivery. The synthesis, crystallinity and purity of nanoparticles were confirmed by UV-Vis Spectroscopy, SEM, XRD, and EDX. Diabetes was induced by using alloxan dose in all mice except healthy mice group. The mice with a weight of 35±15 g were selected and grouped: Positive control group, negative control group, treatment group 1, treatment group 2 and standard treatment group. Positive group was healthy group; no treatment was given. Negative group was given alloxan dose continuously, third diabetic group was treated with titanium oxide nanoparticles, and forth group was treated with cobalt oxide nanoparticles while fifth group was treated with standard dose (Glucophage). The diabetic mice were compared with the treated and healthy group and the efficiency of the treatment was observed. The histopathology of liver and spleen showed better results as compared to the diabetic liver and diabetic mice. The Liver functioning test (LFTs) of diabetic and treated and non-diabetic mice was compared which showed that the lower level of Serum Glutamic Pyruvic Transaminase (S.P.G.T), Alkaline Phosphatase (ALP) and Aspartate Aminotransferase (AST) is a sign of efficient treatment against diabetes. The genes Glucokinase (GK), Insulin Resistance (IR) and Proteinase Kinase (AKT) and Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were targeted against the liver (diabetic, non-diabetic, treated) and gene expression was analyzed using Real-time PCR. The result showed the up regulation of genes in the tissue while down regulation of genes in diabetic liver of mice. Both in-vivo and in-vitro activity of titanium oxide and cobalt oxide nanoparticles showed that these nanoparticles are active anti-diabetic sources of drug delivery.
Artificial neural network based study for photocatalytic degradation of dyes in the presence of 3d transition metal doped zno
(UMT, Lhr, 2023) FADIA KHALID
Extensive research has been carried out on the degradation of organic pollutants through photocatalysis due to the increasing demand for wastewater that is free from pollutants. The results obtained from different experimental runs in photocatalytic degradation can be utilized in data-centric machine learning modeling methods like artificial neural networks. The optimization of 3d transition metal dopants for enhancing the photocatalytic degradation of dyes represents a promising approach in the field of environmental remediation. This study aims to leverage the power of neural networks to optimize the impact of such dopants on the mechanism of photocatalytic degradation. The photocatalytic degradation process is described using both Artificial Neural Networks (ANN). These models incorporated six degradation variables, namely the concentration of composite, concentration of the dye, temperature, pH, irradiation time, and the light intensity or wavelength, as input variables. It uses the degradation percentage of the dye as their output variable. By training neural networks on a comprehensive dataset of experimental observations, the relationships between various process parameters, dopant types, and the efficiency of dye degradation will be modeled and analyzed. The maximum R2 for the outcomes of this research can significantly contribute to the development of more efficient photocatalytic systems for dye removal, ultimately leading to improved environmental sustainability
Bifunctional Core-Shell Structure Zeolitic Imidazole Framework-67@Layered Double Hydroxide (ZIF 67@LDH) for Removal of Organic Pollutant and Creatinine (Bio) Sensing
(UMT, Lhr, 2023) AMMARA SAFDAR
In this research work, microporous zeolite imidazole frmework-67 (ZIF-67), mesoporous layer double hydroxide (LDH) and core-shell mesoporous bifunctional zeolitic imidazole framework-67@layer double hydroxide (ZIF-67@LDH) structure are prepared. Various characterization techniques such as UV-Visible spectroscopy, XRD, SEM, EDX, and N2 adsorption-desorption analysis are employed to investigate the properties of these materials. The bifunctional catalysts prepared in this study are utilized for the removal of organic pollutants from water and also as non-enzymatic electrochemical biosensors for creatinine detection. The core-shell ZIF-67@LDH material exhibited sustainable bifunctionality, effectively removing organic pollutants through both adsorption and photocatalysis under natural sunlight conditions, achieving an impressive removal efficiency of up to 98% without the need for additional additives. Furthermore, the electrochemical behavior and sensing capabilities of ZIF-67@LDH were evaluated using cyclic voltammetry (CV). The catalyst demonstrated low limit of detection (LOD) and high sensitivity for the detection of creatinine. Its porous nature contributed to excellent selectivity, making it suitable for clinical applications.In summary, ZIF-67@LDH proved to be a highly sensitive, stable, cost-effective, and easily fabricated bifunctional catalyst. Its remarkable performance in water remediation and creatinine sensing highlights its potential for practical applications. This interdisciplinary and multidisciplinary research work integrates various fields such as organic chemistry, inorganic chemistry, electrochemistry and analytical chemistry. The aim of this study is to propose and analyze strategies for the removal of organic pollutants from wastewater, addressing the significant social impact and aligning with the “Sustainable Development Goal” (SDG) 6 of UNO “Clean water and sanitation” by contributing to scientific advancements in this field
Comparative analysis of biodiesel produced from tobacco seed oil and cooking oil using homogeneous catalyst
(UMT, Lhr, 2023) SAJID KHAN
The development in utilization of renewable energy sources, like biodiesel, is presented with both opportunities and challenges due to the depletion of petroleum supplies. Biodiesel, a highly promising alternative to fossil fuels, is made from vegetable oils. These vegetable oils have a great deal of potential for producing biodiesel, a sustainable and ecofriendly fuel. Biodiesel synthesis from tobacco seed oil has not received much attention in the past. In this study, tobacco seed oil as well as cooking oil was utilized for the biodiesel synthesis through transesterification reaction with methanol by using an alkaline catalyst. The transesterification reaction was performed with both the oil samples. The reaction temperature was 55oC with 1:6 oil to methanol ratio in the presence of NaOH catalyst (1 wt.%) and reaction duration was 3 hours. The conversion of tobacco seed oil was 86.56%, while that of cooking oil reached 85.9%. GC-MS analysis was performed for characterization and identification of fatty acids alkyl ester compounds. Numerous compounds were identified such as Docosanoic acid, methyl ester, Tetracosanoic acid, methyl ester, Hexacosanoic acid, methyl ester, Stigmasterol, 2,4-Decadienal, (E,E)- and cis-Methyl 11-eicosenoate. Different physicochemical properties of oil as well as their biodiesel were determined including acid value, saponification value and ester value. Some fuel properties of the prepared biodiesels were also determined, like cloud point, flash point, density and viscosity. The produced biodiesels' fuel qualities were examined using American Standard Testing.
Construction of a well-defined S-scheme Ni cos@S-g-C3N4 Heterojunction for Visible Light Driven Photocatalysis and Antimicrobial Performance
(UMT, Lhr, 2023) SHAKEELA RAUF
Direct discharge of waste, including organic dyes from various industries into the water bodies contributes significantly to environmental contamination. A detail research on the photocatalytic materials is much needed that may successfully remove the harmful pollutants from water in order to make water free from such dangerous contaminants. In this respect, CoS based photocatalysts have drawn a lot of attention because of their good stability, excellent conductivity, and relatively small band gap. In the current project, CoS nanoparticles, a series of Ni doped CoS (Ni-CoS) nanoparticles with varying percentage of Ni, and a series of Ni-CoS nanoparticles were made composite with sulphur doped graphitic carbon nitride (Ni-CoS/SCN) with varying concentrations of SCN using an easy, efficient, and affordable co-precipitation technique; however, SCN was synthesized through a thermal degradation process using thiourea as a precursor. Evaluation of synthesized photocatalysts was carried out by cutting edge techniques i.e.; FTIR and XRD. Photocatalytic degradation behaviour of the as prepared photocatalysts was observed by UV-Visible spectrophotometer and the doping of Ni-metal was thought to have contributed to the high rate of degradation of methylene blue, which was used as a standard pollutant dye. The greatest outcomes for doped NPs were from 6% Ni-CoS NPs. while the best photocatalytic activity was achieved by 6Ni-CoS@50 SCN NCs. EIS spectra for CoS, 6% Ni-CoS and 6Ni CoS@50 SCN was observed and they were examined for their antimicrobial performance as well.
Designing Highly Efficient Ternary Nanocomposite ComnsS-g-C3N4 for Bacterial Disinfection and Visible-light Photocatalysis of Organic Dye
(UMT, Lhr, 2023) YASMEEN KHAN
In this project, an eco-friendly, simple and low-cost co-precipitation method was adopted to synthesize pure MnS and a series of Co/MnS NPs with various contents of cobalt (2 %, 4 %, 6 %, 8 % and 10 %). The calcination of thiourea was done at 550 oC to prepare S-g-C3N4 nanosheets. The best doped NPs were then mixed with S-g-C3N4 to prepare a series (10 %, 30 %, 50 %, 70 % and 90 %) of nanocomposites. The band gap (Eg) values of materials were determined by using tauc plot. The photodegradation of MB dye was performed using a UV-Vis. spectrophotometer. According to the results, the doping of 6 % cobalt into the MnS lattice improved the photocatalytic oxidation/reduction. However, the overall best photodegradation was shown by 6Co/MnS@10SCN NCs. The photocatalytic efficiency was enhanced by using 6Co/MnS@10SCN NCs due to the enhancement of charge separation and suppression of charge recombination. Even after three cycles, it was possible to recover the synthesized nanocatalysts with significant % degradation. The structural morphologies of pure MnS, 6 % Co/MnS, S-g-C3N4 and 6Co/MnS@10SCN NCs were examined by using XRD and FTIR. The kinetic study of prepared nanomaterials was performed to determine their rate constant. Bacillus subtilis and Escherichia coli bacteria were selected to test the antibacterial performance of best photocatalysts. It can be inferred from results that the composite synthesis and doping boosted the antibacterial activity of MnS.
Designing of Highly Efficient Mncos@S Nanocomposite with Superior Electrocatalytic Activity for Water Splitting
(UMT, Lhr, 2023) SANAM SHAFIQUE
Hydrogen is a sustainable, eco-friendly, and renewable energy source. Transition metal sulfides incorporated with sulfur doped graphitic carbon nitride (S-g-C3N4) play a vital role in the research of renewable energy resources due to their incredible catalytic activity in water splitting for hydrogen and oxygen evolution reaction, (HER) and (OER) respectively. Here, we designed a highly efficient nanomaterial of Mn-doped cobalt sulfide composite with S-g-C3N4 (Mn/CoS@S-g-C3N4) with superior electrocatalytic activity for water splitting by using a simple co-precipitation method at lower temperature and less time consumption. The electrocatalyst was characterized using the techniques of SEM, EDX, FTIR, and XRD to examine its structure, size, and morphology. Doping and the production of composite materials boost the electrochemical water splitting activity, according to LSV, CV, EIS, and Chronopotentiometry. Three electrode system was used to study the activity of the synthesized electrocatalyst, it was used as a working electrode and exhibited a lower value of overpotential 306 mV for OER and 404 mV HER at 10 mA/cm2 current density in 1 M KOH solution. Moreover, the bifunctional electrocatalyst required less cell potential in an alkaline solution, a remarkable value of Tafel slope, and excellent electrocatalytic activity towards both OER and HER. Results indicated that synthesized electrocatalysts have potential applications for the generation of sustainable energy through water splitting.
Determination of bandgap of period 3, 4, and 5 transition metal dopants on zinc oxide using an artificial neural network based approach
(UMT, Lhr, 2023-03-30) Muhammad Haris Saeed
Artificial intelligence (AI) and machine learning (ML) have rapidly emerged as valuable tools for chemical research, offering new ways to analyze and understand complex chemical systems. This research article investigates the use of adaptive neuro-fuzzy inference system (ANFIS) and multi-layer perceptron (MLP) models to predict the bandgap of transition metal doped zinc oxide (ZnO). The opto-electronic properties of transition metal doped ZnO complexes are of significant interest because of their applications is optoelectronic systems. The MLP and ANFIS models were trained using a dataset of experimentally measured bandgap values and the corresponding structural parameters of the doped ZnO systems. The models were evaluated using statistical measures like the Root Mean Square Error (RMSE) and the Mean Absolute Error (MAE). The results showed that both MLP and ANFIS models were capable of accurately predicting the bandgap of transition metal doped ZnO. However, the ANFIS model demonstrated superior performance with higher accuracy and better generalization ability. The study provides a useful approach for predicting the bandgap of transition metal doped ZnO using machine learning techniques and may contribute to the development of advanced optoelectronic devices.
Devising sustainable methods for recycling industrial polyurethane waste
(UMT, Lhr, 2023) SHAH NOOR ALI
Research is being conducted to recycle and transform polyurethane into a valuable matrix material, addressing a major environmental concern. Buffing dust, often a byproduct of leather finishing processes, was utilized to enhance certain properties. This research focused on buffing dust and polyurethane waste for use in the construction industry. In the process of fabricating thermal insulation panels, a mixture of fresh polyurethane, polystyrene, buffing dust, and alumina nanoparticles was used to produce the PUC sample. On the other hand, the WPUC sample was synthesized by using waste polyurethane, glass fiber, polystyrene, buffing dust, and alumina nanoparticles. The PUC sample showed water absorption of up to 38%, while the WPUC sample displayed up to 44.6%. The FTIR study indicated that the both samples show the distinctive vibration of the –OH group of the amino acid found in discarded leather. SEM analysis of both samples showed that the addition of glass fiber and buffing dust led to the formation of voids. EDX analysis revealed that the PUC composite sample consisted of 2.38% Oxygen and 48.53% Carbon, while the WPUC composite material contained 1.94% Oxygen and 46.18% Carbon. Thermogravimetric analysis revealed that the PUC and WPUC samples exhibited thermal stability till 280 °C and 350 °C respectively. This effort aligns with the Sustainable Development Goal (SDG) No. 11, which emphasizes the creation of sustainable cities and communities.
DFT Investigation for Sensing of Toxic Gases, Chemical Warfare Agents, and Anticancer Drugs on B2N2C2 Nanosheet
(UMT, Lhr, 2023) Maira Amjad
Inorganic nanosheets are a part of dynamic research with great prospective for developing advanced materials that possess unique properties and functionalities. One such type of inorganic nanosheet is B2N2C2, which consists of three atoms that includes boron atoms having carbon atoms and nitrogen atoms that are organized in a framework which is hexagonal in structure, also known as hexagonal BCN or 2DBCN. B2N2C2 nanosheet exhibit exceptional thermal stability, high mechanical strength, and excellent electrical conductivity, making them highly promising for a number of uses, e.g. in electronics, energy storage devices, and sensors. Ongoing research into B2N2C2 nanosheets aims to explore their unique properties and potential applications in advanced materials. In this context, we have performed a study to investigate the sensing capabilities of B2N2C2 nanosheets using Density Functional Theory (DFT). Our findings indicate the physiorption of various analytes (Toxic Gases, A-series of CWA and anti-cancerous drugs) on the surface of the nanosheet. This shows that the B2N2C2 sheet is sensitive towards the analytes due the variation in energy gaps of HOMO-LUMO and charge transfer. Non covalent interactions of analytes and B2N2C2 sheet reveals by RDG spectra. The nature of noncovalent interactions was determined mainly to be van der Waals through NCI analysis. Among all the complexes NO2@B2N2C2 shows the higher values of interaction energy of -63.56 kcal/mol and Eg (eV) which is 3.85 eV. NBO charge analysis shows transfer of charges between pure B2N2C2 sheet and selected analytes. These properties shed light on the potential of B2N2C2 nanosheets as highly sensitive sensors with various practical applications.
Fabrication of CoxV1-xO8 with Sulphur Doped Graphitic Carbon Nitride for Energy Storage Devices
(UMT, Lhr, 2023) MUHAMMAD RASHEED
Now a day's world is moving toward sustainable energy development as fossil fuels are agility depleting. The most advance method of sustainable energy are the energy storage devices due to their long life cycle and high energy density. Recently lithium ion batteries are widely used in portable electric devices like laptop computers, vehicles and cell phones. Solid state rechargeable batteries are usually composed of electrolyte, anode and cathode. However, can't meet the requirement due to its poor capacity and low voltage. Usually, the negative charge electrode of traditional Li-ion cell is a graphite and it composed of carbon. However, positively charge electrode is mostly composed of MnO2. Li-salt act as an electrolyte in any organic solvent. During charging and discharging, there is a separator between cathode and anode which prevent both electrodes from shorting. A metal piece known as collector helps to separate these electrodes from external electrical circuit. Metal vanadates has received great attention as ideal anode materials for energy storage devices due to high capability of lithium ions storage. A variety of metal vanadates like Zn3V2O8, Cu3V3O8, and FeVO4 were synthesized and investigated. Cobalt vanadate is an important class of metal vanadates, having high lithium storage capacity. Various methods are used for the synthesis of these vanadates. Some of these methods include solid state and electrospinning. These vanadates have various applications i.e electrode sensing, electrocatalytic oxygen evolution reaction, water oxidation and in the field of Li-ion batteries. Among all these, hydrothermal method is a simple, cost effective and environment friendly method. Another advantage of this method is that all types of vanadates can be prepared from this method. In order to increase the storage capacity of lithium ion batteries, Co3V2O8 nanoparticles were fabricated with S-g-C3N4, a single step hydrothermal method was selected to synthesize cobalt vanadate nanoparticles, a series of cobalt vanadate (CoxV1-xO8) nanoparticles were synthesized by changing the weight percentage of cobalt (1, 2, 3, 4 and 5 wt %) and composite of 2 % Co3V2O8 on S-g-C3N4 by changing weight percentage of S-g-C3N4 (10, 30, 50, 70 and 90 wt %). Annealing temperature changes the surface area of the bulk cobalt vanadate doped S-g-C3N4 samples. Nickel foam was employed as working electrode. Nickel foam was modified with cobalt vanadate doped S-g-C3N4 nanocomposite and used to perform electrochemical activity. The surface morphology and structure of synthesized material were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared (FT-IR) spectroscopy. The XRD patterns showed the synthesized material is of high crystallinity with average crystallite size of 48.16 nm. The crystallite size was calculated by using Scherer equation. The SEM images revealed that cobalt vanadate doped S-g-C3N4 nanocomposite have uniform surface morphology. The FT-IR spectroscopy explained stretching vibration of all possible bonds present in cobalt vanadate doped S-g-C3N4. In comparison to all of the prepared samples, composites of 30 % cobalt vanadate doped S-g-C3N4 gives high specific capacity toward anodic efficiency of energy storage devices. Moreover, cobalt vanadate doped S-g-C3N4 gives high discharge specific capacity of 432 mAhg−1 at a current density of 1.0 Ag−1 and 326 mAhg−1 at a current density of 2.0 Ag−1. The cobalt vanadate doped S-g-C3N4 also delivered a remarkable energy density of 96 Wh/Kg with a power density of 275 W/Kg. Thus present synthetic approach provides a solution to enhance the cyclic stability and specific capacity of the electrode for the lithium ion batteries. Studying their electrochemical properties, it is suggested that 30 % cobalt vanadate doped S-g C3N4 would be used as potential anode material for sustainable energy development in energy storage devices in future.
Fabrication of nickel doped cobalt ferritespolyaniline composite for wastewater remediation
(UMT, Lhr, 2023-11-22) SEHRISH KHALID
The amount of toxic pollutant is increasing day by day to an alarming level. This demands a facile and economical way to degrade those deadly contaminants. This study provides a valuable and facile pathway to purify waste water from toxic dyes with a cheap and environmentally friendly approach. Cobalt ferrites doped with nickel were synthesized employing the coprecipitation technique. In this research, varying concentrations of nickel (2%, 4%, 6%, 8%, and 10%) were incorporated into the cobalt ferrite samples. Composites of these nickel doped ferrites with polyaniline were obtained by stirring the ferrites and polyaniline in distilled water as suspension followed by sonication for one hour. The suspension was filtered, vacuumed dried and characterized using SEM with EDX, FTIR and XRD. Prepared nickel doped cobalt ferrites polyaniline composites degradation percentage was calculated via UV- Visible spectroscopy which indicated the degradation capacity was increased via increased percentage of nickel metal. Prepared nickel doped cobalt ferrite polyaniline composite degradation percentage was calculated via UV-Visible spectroscopy which indicated the degradation capacity was increased via increased percentage of nickel metal. The FTIR spectra confirmed the successful integration of nickel onto the surface of PANI. XRD spectra indicated the formation of a single-phase spherical structure. SEM analysis coupled with EDX revealed that the synthesized nanoparticles were uniformly dispersed and spherical, with their diameter increasing as a result of nickel doping. In summary, this study suggests that nickel-doped cobalt ferrite nano composites with PANI could serve as promising candidates for efficiently degrading toxic waste in wastewater. This efficiency is attributed to the incorporation of polyaniline into nickeldoped cobalt ferrites, making the approach sustainable and environmentally friendly.
Fabrication of novel vildagliptin-loaded zinc oxide nanoparticles for anti-diabetic activity
(UMT, Lhr, 2023) ABDUL SAMAD
The aim of the current study was to synthesize vildagliptin loaded ZnO nanoparticles for enhanced efficacy in terms of increased retention time, minimize side effects and increased hypoglycemic effects. Diabetes mellitus is the fastly prevailing disease throughout the world. Vildagliptin is the standard drug which is used for the treatment of diabetes. But the drug has certain limitations associated with it which includes short half-life and high dosage frequency. Now a days, Nanotechnology has revolutionized in every field of life. In medicine, nanoparticles are used as safe drug carriers, as nano-medicines with increased bioavailability, in tissue engineering and in diagnosis of diseases. Various nanoparticles like ZnO nanoparticles itself have medicinal applications. In this work, ZnO nanoparticles were synthesized by precipitation method and then drug vildagliptin was loaded on them by batch adsorption method. Ultraviolet Visible spectroscopy, Fourier transform Infra-red spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), High performance liquid chromatography (HPLC) and Energy Dispersive Xray (EDX) analysis were performed for the characterization of synthesized Vildagliptin loaded ZnO nanoparticles. The morphology of the synthesized drug loaded nano-material was analyzed by SEM which shows the formation of product with flaky texture. The crystallinity of drug loaded nano-materials was analyzed by XRD which gave the average crystalline size of 21.94 nm. EDX analysis detected the presence of Carbon, Oxygen, Zinc and Nitrogen in the product. The drug loading efficiency was determined by using HPLC method. The maximum adsorption efficiency of 58% was obtained. Further, In vitro anti-diabetic activity was assayed by determining the α-amylase and DPP IV inhibition activity of the product formed. The formulation gave maximum inhibition of 82% and 94% of α-amylase and DPP IV respectively at concentration of 1000 µg/ml. The inhibition of α-amylase can be attributed to synergistic effect of ZnO nanoparticles and vildagliptin.
Fabrication of Si12C12 Nanocage with First Row Transition Metals to act as Single Atom Catalyst for HER reaction
(UMT, Lhr, 2023) Saira Rafiq
In this research work, doped nanocage of silicon carbide is investigated. The adsorbtion of hydrogen at doped TM@SiC reveals that stability of nanocage is significantly improves. In this work, we investigated the many properties such as geometry, electronic properties, NBO, NCI plots of various doped nanocages of Silicon Carbide (Zn@ Si12C12, Fe@ Si12C12, Co@ Si12C12, Cu@ Si12C12 and Ni@ Si12C12). All calculations are calculated at the same level of B3LYP/631-G(d). All the doped structures reveal that nanocage complexes have highest interaction energies from 0.4 to -0.69 eV and Cu@Si12C12 plays an excellent role in HER due to values 0.17 eV which is near to zero. Cu@Si12C12 shows the excellent activity in stability and HER due to lower values -3.30 eV. According to NBO calculations, it is observed that charge transferred from doped transition metals towards nanocage which leads to stability of nanocage. After H adsorbtion, NBO charge transfer to hydrogen which shows the adsorbtion properties of H. In case of HOMO-LUMO energy gap, it is observed that nanocage of doped transition metals have small energy gap from 0.0 eV to 2.7 eV but after adsorbtion of hydrogen, this energy difference between the gap leads to change from 0.1 eV to 3.7 eV which also verify the stability of nanocage. DOS spectra’s showed the formation of new bonds due to difference in electron density that shifts. NCI plots also explained the different types of bonding in doped nanocage.
Fabrication of SNO2@znoCarbon Foam Nanocomposite for Efficient Degradation and Antibacterial Activity
(UMT, Lhr, 2023) RAHEELA RAMZAN
In this research, SnO2@ZnO/CF nanocomposite fabricated by one pot facile synthesis followed the coprecipitation route. The nanocomposite was characterized by FTIR, XRD, TGA, SEM and EDX revealed functional group, crystalline structure, thermal stability, morphology and, conformation of elements respectively. As prepared nanocomposite has a high efficiency to degrade the methylene blue on sunlight light irradiation as compared to the individual SnO2 and ZnO/CF nanocomposite. SnO2@ZnO/CF nanocomposite suppressed the charge recombination and enhanced the charge separation which increases the photocatalytic degradation activity upto 100 %. The catalyst amount, light exposure, concentration of MB was optimized. The nanocomposite can be recovered after several cycles and demonstrated degradation rate around 92 %. Antibacterial activity was evaluated against Gram-negative bacteria (E. coli) and Gram-positive (Bacillus subtilis). The high antibacterial activity of the SnO2@ZnO/CF nanocomposite is attributed to the generation of the reactive oxygen species (ROS) and the release of the metal’s ions. These reactive species destroyed the cell wall of the bacteria and kill them. Thus, it has been proven that the SnO2@ZnO/CF nanocomposite displayed high photocatalytic activity for the degradation of organic dyes, with high antibacterial activity.
Micro determination of minerals and anti-oxidant activity in different mushrooms of swat valley by spectroscopic techniques
(UMT, Lhr, 2023) Sana Ashraf
Mushrooms are known to mankind since early human civilization and gradually gained importance due to their medicinal and nutritional properties. These are also origin of mineral nutrients, proteins and carbohydrates Mushrooms are important fungi used in complementary medicine. Helvella spp. are found most abundantly in Himalayan moist temperate forests of Pakistan. Native people are using these mushrooms since centuries. For the first time, mineral analysis and anti-oxidant activities of Helvella spp. have been reported from Pakistan. This study gives attention to expose their mineral profiles by Flame photometery, Atomic absorption spectroscopy and Spectrophotometry. Biological activities focusing on antioxidant activities based upon lyophilized sequential extracts and traditional preparations attain from the fruit bodies of these mushrooms. The present study revealed that Helvella acetabulum are most enrich in sodium (53mg/100mg) and Helvella paraphysiorquata showed highest trace element iron (0.51mg/100mg) concentration. The most active oxygen inhibitor and enzyme inhibitory extracts were shown by H. paraphysitorquata. Information obtained from this data reveals that H. paraphysitorquata used as raw materials in food, pharmaceutical industries, nutraceutical and biotherapeutic. The results suggested that mushrooms can be ingested as a functional food and employed as a therapeutic element due to its bioactive substances and its well-balanced nutritional profile. Hopefully the selected mushroom species will further be analyzed and used it in daily diet to reduce the deficiency of micronutrients in people.
MIL-101(fe) derived cofe nanomaterials for electrocatalytic oxygen reduction reaction
(UMT, Lhr, 2023) WARDA ASHRAF
The combustion of fossil fuels has long been recognized as a major contributor to the increase in greenhouse gas emissions, particularly carbon dioxide (CO2), leading to the capture of heat returning from the Earth's surface and subsequent global warming. As a response to the urgent need for clean and sustainable energy, fuel cells and metal-air batteries have emerged as proven technologies. These systems rely on electrochemical reactions, with the oxygen reduction reaction (ORR) playing a pivotal role in their overall performance. Understanding the factors influencing the activity and selectivity of ORR catalysts is crucial for the development of efficient and selective catalysts, contributing to the advancement of clean energy applications. In this context, the exploration of various carbon supports, Fe precursors, and the role of nitrogen content has become an integral aspect of catalyst design. The ongoing quest for enhanced catalyst performance has led to innovative approaches, and one such approach involves the synthesis and modification of metal-organic frameworks (MOFs). In this particular study, the MOF MIL-101 (Fe) serves as the precursor for the synthesis of an efficient ORR catalyst. The MOF is subjected to a controlled sonication process with melamine, cobalt nitrate hexahydrate (Co(NO3)2.6H2O), and iron nitrate nonahydrate (Fe(NO3)3.9H2O). The resulting composite undergoes calcination under an argon atmosphere, leading to the creation of a highly effective catalyst for ORR. By adjusting the concentration of Fe(NO3)3.9H2O while keeping the concentrations of MIL-101, Co(NO3)2.6H2O, and melamine constant, various materials with distinct ratios are synthesized. Characterization of the resulting materials conducted through powder X-ray diffraction studies, providing insights into their structural composition and crystallographic features. The catalytic activity of these materials further assessed using a three-electrode system with a rotating disc electrode (RDE) serving as the working electrode. Among the synthesized materials, denoted as Co/Fe@1, Co/Fe@2, Co/Fe@3, and Co/Fe@4, Co/Fe@3 stands out as a particularly effective catalyst for selective O2 reduction. Co/Fe@3 exhibits superior ORR activity when tested in a 0.1 M KOH solution, showcasing comparable performance to the benchmark catalyst (20 wt% Pt/C). Key electrochemical parameters, such as onset potential of 0.99 V, a Tafel slope of 57 mV dec-1, current density of 5.22 mAcm-2, and a half-wave potential of 0.87 V, highlight the efficacy of the synthesized material. Notably, this material opens a pathway for the fabrication of effective ORR catalysts based on iron, a metal traditionally deemed less active in ORR processes. In summary, the synthesis and modification of MOFs for the development of efficient ORR catalysts represent a promising avenue in the pursuit of sustainable energy solutions. The meticulous exploration of various parameters in the synthesis process, coupled with comprehensive characterization and electrochemical assessments, contribute to the ongoing advancements in the field of catalyst design for clean energy applications.
Preparation of Cu-SiO2g-C3N4 Composite for the Removal of Pollutants from the Wastewater
(UMT, Lhr, 2023) HAFIZA HINA JAVED
In this work, copper-doped silica (Cu-SiO2)@g-C3N4 has been prepared to get a composite material. The composite material served as novel catalyst for the photocatalytic degradation (upto 99%) of a model dye methylene blue. In the presence of sunlight. In addition, the catalyst successfully inhibited some famous types of pathogens (E.Coli.and B. Subtilus) present in the polluted water. The composite material was characterized using various techniques for the surface morphology, stability and particle size. These analyses included spectroscopy, X-ray diffraction, scanning electron microscopy, and elemental analysis. The prepared composite material has the ability to reduce charge recombination and increase charge separation during the excitation in the presence of sunlight. The production of reactive oxygen species (ROS) at the surface of metal ions were thought to be responsible for the powerful antibacterial capabilities of the Cu-SiO2/g-C3N4 combination. These reactive species efficiently pierced the cell walls of the bacteria, which ultimately led to their extinction. Our results emphasize the strong antibacterial capabilities and extraordinary photocatalytic activity of the Cu-SiO2/g-C3N4 composite in degrading organic dyes, indicating its potential for a wide range of environmental and biological applications.
Removal of commercial dyes from aqueous media by adsorption on biochar prepared from beans of cassia fistula
(UMT, Lhr, 2023) SYEDA MEHAK ZAHRA NAQVI
Commercial dyes used in textile industry for dying the fabric are usually toxic and damage aquatic life in water significantly. Untreated industrial effluents flushed out in water channels are considered a major source of water pollution. In this work three commercial dyes: Safranine, Crystal Violet and Orange-2 are removed from aqueous media by adsorbing them on biochar. The biochar used in this work was prepared from a locally grown decorative plant Cassia Fistula commonly known as Amaltas in local language. This plant has been abundantly found in all areas of Punjab (Pakistan). In spring yellow clusters of flowers can be easily seen showering on the branches of this plant. On the end of spring season, one to two feet long beans of dark brown colour containing seeds are found hanging along with the branches of the plant. To prepare the biochar the dried beans were collected from the plants available in the campus (Punjab University, Lahore). The seeds were removed by crushing the beans and the skull was dried and pyrolyzed in a furnace under control temperature and little presence of air. The black lumps of biochar obtained were ground and sieved. All the three dyes mentioned above were adsorbed on this mass by shaking in aqueous media and under different conditions of temperature, pH, adsorbent dose and shaking speed and time etc. It was observed that under optimum conditions each of the above mentioned dyes can be eliminated from 95% to 99% in aqueous media. This method of removing the toxic dyes by adsorbing on biochar prepared by the pyrolysis of an indigenous plant material was found a simple, fast and inexpensive.
Removal of fluoride by using biochar; a step toward sustainable environmental remediation
(UMT, Lhr, 2023) GHAZALA YASEEN
The thermochemical conversion of agricultural waste to biochar opens up new possibilities for environmentally sustainable waste management. Biochar is widely applicable in the field of waste-water treatment because of utilizing a variety of physical and chemical activation methods to change its structural and physicochemical properties to fit the ultimate use. The main purpose to conduct this study was to remove the fluoride ion by using banana and grapefruit peels biochar. Biochar was chemically treated with ZnCl2 and sodium dodecyl sulfate. Ion selectiveelectrode was used for quantitative study the batch wise adsorption of fluoride optimizing by different parameters such as; time contact, adsorbent dosage, pH, anion concentration as well as temperature. Different isothermal, kinetic and thermodymics models were studied in order to investigate the adsorption behavior of biochar. Biochar was characterized by Scanning electron microscope (SEM) for surface morphology, FT-IR for functional groups and Thermogravimetric Analysis (TGA) for the thermal stability. Carbon, Hydrogen, nitrogen and Sulfur was used to scrutinize the elemental conformation of biochar obtained from agricultural waste. The results showed that biochar prepared from banana and grapefruit peels are considered among eco-friendly and inexpensive adsorbents to eliminate fluoride ion from the aqueous medium.

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