Department Of Physics
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Item Predominated capacitive behavior of Ag-doped magnesium vanadate as a novel electrode material for supercapacitors(Elsevier Ltd, 2023-06-11T00:00:00) Umair, Muhammad; Shad, Naveed Akhtar; Hussain, S.; Jilani, Asim; Sajid, Muhammad Munir; Arshad, Muhammad Imran; Hasnain Rana, Hafiz Talha; Sharma, Surender Kumar; Mishra, Yogendra Kumar; Javed, YasirTransition metal vanadate nanostructures are getting significant importance as an efficient electrode material for modern energy storage applications. In this work, a simple hydrothermal method is employed for the synthesis of magnesium vanadate (MgV2O5) and Ag-doped magnesium vanadate (Ag doped MgV3O8) nanomaterials. The X-ray diffraction (XRD) analysis reveals the formation of an orthorhombic structure for magnesium vanadate, whereas the Ag-doped magnesium vanadate results in a monoclinic structure. Interestingly, the optical bandgap is observed to increase from 2.85 eV to 3.92 eV with the increase in Ag-doping as revealed from Tauc's plot of the UV-visible absorption spectrum. The electrochemical performance of magnesium vanadate electrodes is thoroughly investigated by cyclic voltammetry (CV), Galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy. The Ag-doped magnesium vanadate shows higher specific capacitance (Cs = 706 Fg?1) in comparison to undoped (325 Fg?1) at a current density J = 5 Ag?1. The theoretical investigations through Dunn's model demonstrate a major contribution arises from surface-controlled processes, which increase as high as 91% at scan rate of 60 mVsec?1. Our findings indicate that Ag-doping significantly improves the overall electrochemical response of magnesium vanadate as an efficient electrode material for supercapacitor applications. � 2023 Hydrogen Energy Publications LLCItem Bi-phasic BiPO4 prepared through template-assisted hydrothermal method with enhanced electrochemical response for hybrid supercapacitor applications(Springer Science and Business Media B.V., 2023-03-27T00:00:00) Monteles, Iara A.; Penha, Bruno V.; Fonseca, Weliton S.; Silva, Let�cia M. B.; Santos, Evelyn C. S.; de Souza, Luiz K. C.; Santos, C.C.; de Menezes, A.S.; Sharma, Surender K.; Javed, Yasir; Khawar, Muhammad R.; Tanaka, Auro A.; Almeida, Marcio A. P.Abstract: We report the structural evolution of BiPO4 prepared in aqueous under different synthesis conditions viz., templates and temperatures to explore their electrochemical performance for supercapacitor applications. The templates [(hexadecyltrimethylammonium bromide (CTAB)), sodium dodecyl sulfate (SDS)] were added in bismuth precursor solution at 60��C, alternatively ethylene glycol (EG), a less toxic additive was incorporated at 90��C. BiPO4 exhibits a monoclinic phase, whereas a hexagonal structure was observed with the addition of the templates SDS and CTAB. Interestingly, both monoclinic and hexagonal phases were obtained by the addition of EG. The presence of mixed phase was thoroughly validated through Raman spectra, where vibrational modes for both monoclinic and hexagonal phases of BiPO4-EG were witnessed. The effect of template was clearly seen through electron microscopy with a rod-like morphology with (no template) and unfaceted (template). The electrochemical behavior of the synthesized materials was investigated, and it was found that the mixed structure of BiPO4-EG exhibited the highest specific capacity (167.15 C�g?1) at a scan rate of 5�mV�s?1, good capacitance retention at high current densities of up to 10 A�g?1 and the lowest electrochemical series resistance (ESR) of 57 ?. Graphical abstract: [Figure not available: see fulltext.]. � 2023, The Author(s), under exclusive licence to Springer Nature B.V.Item Probing the optical and magnetic modality of multi core-shell Fe3O4@SiO2@?-NaGdF4:RE3+ (RE = Ce, Tb, Dy) nanoparticles(Elsevier B.V., 2023-02-22T00:00:00) Shrivastava, Navadeep; Ospina, Carlos; Jacinto, Carlos; de Menezes, Alan S.; Muraca, Diego; Javed, Yasir; Knobel, Marcelo; Luo, Zhiping; Sharma, Surender KumarA robust yellowish-green emitting multi core-shell Fe3O4@SiO2@?-NaGdF4:RE3+ (RE = 5% Ce, 5% Tb, x% Dy; x = 1, 5 and 10 mol.%) nanoparticles (NPs) containing both magnetic and luminescence modalities, are synthesized using simple, fast and efficient microwave-assisted hydrothermal method. The Rietveld analysis of X-ray diffraction and high-resolution transmission electron microscopy provides an average crystallite size of ?30 nm, confirming the successful coating of the ?-NaGdF4 hexagonal phase over Fe3O4. The detailed photoluminescence investigation suggests a down-converting energy transfer process, Ce3+?Gd3+?Tb3+? Dy3+ in which Gd3+ ions play a significant intermediate role assisted by Tb3+. The excitation spectra consist of dominant broadband at ?252 nm due to Ce3+ (4f�5d), two sharp lines at ? 271 nm, and ?311 due to Gd3+ (8S7/2?6IJ and 6PJ), and frail f?f transitions due to Tb3+ and Dy3+ ions. The excitation at ?252 nm fetches weak and sharp emission of Gd3+ ions at 310 nm, weak broad emission of Ce3+ (300�400 nm), and strong emission color lines of RE3+ (400�700 nm) due to characteristic transitions of Tb3+ (5D4?7FJ, J = 6�3), and Dy3+ (4F9/2�6H15/2, 6H13/2), respectively. The quenching phenomenon is observed due to concentration, and back transfer energy is proposed. The magnetic hysteresis loops display superparamagnetic behavior at 300 K and ferromagnetic ordering at 2 K with a remarkable difference in their magnetization values and confirming the blocking temperatures around physiological temperature ranges. The magneto-luminescence characteristics of the bifunctional system can be easily manipulated under an external magnetic field and suggest an efficient candidate for hybrid medical imaging such as MRI plus X-ray imaging and radiation detection. � 2023 Elsevier B.V.Item Tuning Structural and Optical Properties of Copper Oxide Nanomaterials by Thermal Heating and Its Effect on Photocatalytic Degradation of Congo Red Dye(Iranian Institute of Research and Development in Chemical Industries, 2022-05-01T00:00:00) Rehman, Sidra; Akhtar Shad, Naveed; Munir Sajid, Muhammad; Ali, Khuram; Javed, Yasir; Jamil, Yasir; Sajjad, Muhammad; Nawaz, Ahmad; Kumar Sharma, SurenderIn this study, Copper oxide (CuO) nanoparticles (NPs) were prepared using the chemical co-precipitation method and treated at different calcination temperatures. The synthesized CuO NPs have been calcinated at 300 �C, 500 �C, and 700 �C. The X-Ray Diffraction (XRD) results exhibited a decrease in the width of the principle diffraction peak with the temperature rise. Crystallite size was determined by Scherrer�s formula, whereas, the Williamson-Hall method presented drastic variation in size indicating the creation of lattice strain with the rise in calcination temperature. Scanning Electron Microscopy (SEM) images showed an increase in grain size and vary from 170 nm � 430 nm. X-ray Energy Dispersive Spectroscopy (EDS) results indicate the formation of CuO NPs and relative Cu contents increased (52.9 to 72.5 Atomic percentage) with temperature. Optical properties are also affected by the calcination temperature and a reduction in bandgap is observed with the increase in temperature. Fourier Transform Infra-Red (FT-IR) spectroscopy spectra of different samples showed identical bonding behavior and no apparent change in bonding was observed. Photo-degradation of Congo Red dye was performed with CuO NPs treated at different temperatures and NPs treated at 500 �C, have shown maximum degradation efficiency in 75 min under visible light. � 2022, Iranian Institute of Research and Development in Chemical Industries. All rights reserved.Item Magnetic Ferrites-Based Hybrids Structures for the Heavy Metal Removal(Springer Science and Business Media Deutschland GmbH, 2021-10-29T00:00:00) Abbas, Muhammad Khawar; Yasin, Effat; Sajid, Muhammad Munir; Shad, Naveed Akhtar; Akhtar, Kanwal; Manhas, Anita; Sharma, Surender K.; Javed, YasirAdsorption is a major process for heavy metal removal and the research trend is focused toward the applications of new technologies in order to intensify the already existing processes. Intrinsic properties of magnetic materials (arrangement and surface-to-volume ratio) of adsorbate and adsorbent are critical for satisfactory results. Magnetic field strength plays an important role as it indicates the alignment of spins with the magnetic field to provide adsorbate mobility and generate heterogeneity at adsorbent surface. Applications of magnetic field for intensification of adsorption process provide environment friendly, safe and economic alternative. This chapter describes different types of magnetic ferrites-based hybrids for heavy metal removal. Surface modification of magnetic nanohybrids through different surface modification strategies and general adsorption mechanisms for different types of pollutants are discussed comprehensively. Major thrust of this chapter is to provide information about different features of magnetic ferrites for their potential application as adsorbent for heavy metal removal. � 2021, Springer Nature Switzerland AG.Item Potential of Iron Oxide Nanoparticles as Drug Delivery Vehicle(Springer Science and Business Media Deutschland GmbH, 2021-10-29T00:00:00) Hassan, Muhammad Aamir; Khan, Aqib Zafar; Sajid, Muhammad Munir; Javed, Yasir; Ullah, Asmat; Shad, Naveed Akhtar; Sharma, Surender K.; Shafique, Muhammad; Sarwar, MuhammadNanotechnology has introduced new techniques and therapeutic approaches for the treatment of different cancer types. Current cancer-curing drugs have many limitations such as use of high concentrations, effects on other cells, and non-confinement at cancer sites, which reduce the efficacy of drugs and also induce toxic effects in other normal cells. Nanomaterials have provided new ways to increase the efficacy of already used cancer drugs by providing drug delivery systems. Anticancer drugs can be encapsulated/attached with the nanomaterials and delivered at specific sites and cells under certain microenvironment conditions. Among metallic oxide nanoparticles, iron-based particles have shown great potential in drug delivery and at the same time for cancer treatment by producing localized heat. Therefore, researchers have focused on iron oxide nanoparticles as drug delivery vehicles. This chapter highlights the synthesizing methods of iron oxide nanoparticles such as co-precipitation, thermal decomposition, microemulsion, sol�gel, and additional chemical methods including hydrothermal, sonochemical decomposition, and electrochemical for their wide range of biomedical applications. It also provides a brief overview of recent developments in iron oxide nanoparticles, some limitations in the explored research areas. and suggests future directions to overcome these limitations. � 2021, Springer Nature Switzerland AG.Item Progress in Ferrites Materials: The Past, Present, Future and Their Applications(Springer Science and Business Media Deutschland GmbH, 2021-10-29T00:00:00) Manhas, Anita; Singh, Mahavir; Hussain, Muhammad Irfan; Javed, Yasir; Sharma, Surender K.Ferrite is a magnetic substance consist essentially of an oxide of iron combined with one or more other metals such as manganese, copper, nickel, or zinc. They are being routinely utilized especially in electronic devices owing to its good magnetic properties along with high resistivity. � 2021, Springer Nature Switzerland AG.Item Modern Applications of Ferrites: An Important Class of Ferrimagnetic System(Springer Science and Business Media Deutschland GmbH, 2021-10-29T00:00:00) Gomes, Gabriel Alves; Akhtar, Kanwal; da Costa, Gisela Lara; Javed, Yasir; Sharma, Surender K.Magnetic nanoparticles (MNPs) have been used in engineering applications for different purposes in the last few decades, increasing their relevance recently on biomedical studies, with alternative treatments to most complex diseases, and microelectronic fields, as an excellent way to improve aspects such as thermal and electric conductivity. The use of nanomagnetic ferrite particles in cancer therapy and to control antibacterial agents is also noteworthy, because of their advantages in terms of resistance to temperature variations, chemical stability, and long-term durability. One of the promising applications of these nanoparticles includes water-purifying systems. In this chapter, those outstanding aspects of nanoparticle ferrites were treated since their very applicable point-of-view. In this sense, the structure properties of this class of materials are a very important matter to discuss, investigating how their unique ferrimagnetic face centered behavior could directly influence their potential in technological fields and innovative medical treatments. � 2021, Springer Nature Switzerland AG.Item Enhanced Electrochemical Performance of Hydrothermally Synthesized NiS/ZnS Composites as an Electrode for Super-Capacitors(Springer, 2021-08-22T00:00:00) Asghar, Ali; Yousaf, Muhammad Imran; Shad, Naveed Akhtar; Munir Sajid, M.; Afzal, Amir Muhammad; Javed, Yasir; Razzaq, Aamir; Shariq, Mohammad; Gulfam, Qurrat-ul-ain; Sarwar, Muhammad; Sharma, Surender K.In this study, nickel sulfide (NiS), zinc sulfide (ZnS), and their composites have been synthesized by using surfactant driven hydrothermal method. Synthesized materials are investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy, UV�Vis and Photoluminescence spectroscopy. XRD results have shown the presence of corresponding structural planes. Crystallite size was much smaller (15�nm) in the case of ZnS nanomaterials, whereas, composite materials have shown size comparable to NiS nanomaterials. SEM images presented morphology of star-like, spherical, and mixture of two for NiS, ZnS, and NiS/ZnS nanocomposites respectively. EDX spectrum of composite materials showed Nickel, Zinc, and Sulfur, indicating the purity of the synthesized composite. Electrochemical measurements i.e. cyclic voltammetry and galvanostatic charge�discharge were determined for all three materials. Maximum specific capacitance is obtained as 1594.68 F�g?1 at a scan rate of 5�mV�S?1 for NiS/ZnS composite materials whereas a charging/discharging time of 461.97�s is observed. The composite materials have shown 95.4% retention for applied for 3000 charging�discharging cycles. The favorable behavior of NiS/ZnS composites indicated their potential as an electrode material for pseudo-capacitors. � 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Item Facile synthesis of Bi2WO6/rGO nanocomposites for photocatalytic and solar cell applications(Elsevier Ltd, 2021-02-22T00:00:00) Shad, Naveed Akhtar; Sajid, Muhammad Munir; Afzal, Amir Muhammad; Amin, Nasir; Javed, Yasir; Hassan, Safia; Imran, Zahid; Razaq, Aamir; Yousaf, Muhammad Imran; Munawar, Anam; Sharma, Surender KumarManipulation of materials at nanoscale provides many new and enhanced properties to be utilized for multifaceted applications, which was not possible before. In this study, we fabricated Bi2WO6/rGO composites using hydrothermal method. The obtained composites were then examined using different analytical techniques such as XRD, SEM, TEM, FTIR, XPS, BET, and AFM. Their catalytic properties were assayed by carrying out the degradation of organic dye Rhodamine B (RhB) and employed as a hole transport layer (HTL) in the perovskite solar cells. The fabricated nanocomposites were able to degrade 98% of dye solution within 4 h. The improved photocatalysis is attributed to a large surface area ~86.06 m2/g with pore size 7.812 nm and enhanced separation of electron-hole pair charges due to rGO sheets. The open-circuit voltage was increased up to 0.94 V when composite materials were used as HTL. The power conversion efficiency (PCE) of the device was enhanced to 11% because of the improvement in the interface quality between HTL and the perovskite layer. It is conceived that the fabricated nanomaterial may show excellent potential in smart solar cell applications. � 2021 Elsevier Ltd and Techna Group S.r.l.