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Öğe A dual-emitting Rhodamine B-encapsulated Zn-based MOF for the selective sensing of Chromium(VI)(Pergamon-Elsevier Science Ltd, 2024) Shah, Javed Hussain; Sharif, Shahzad; Sahin, Onur; Shahbaz, Muhammad; Azeem, Waqar; Ahmad, SaeedA Rhodamine B-Zn-MOF composite (RhB-Zn-MOF) with dual emission intensity was synthesized through one pot synthesis by in -situ encapsulation of Rhodamine-B dye on a new Zn-MOF metal-organic framework [(Zn (OAc)2(4-BrIPh) (1,10-phenonthroline)(H2O)].H2O, (4-BrIPh = 4-Bromoisophthalic acid). The synthesized encapsulated material was characterized by elemental analysis, FTIR, UV-Visible spectroscopy, TGA, single crystal and powder X-ray diffraction and photoluminescence spectroscopy. The results showed that the synthesized composite, RhB-Zn-MOF could be used as an efficient probe for the selective sensing of Cr(VI) in the presence of Cr(III) as well as other metal ions.Öğe Crystal structures, DFT and fluorimetric study of a dual nature Schiff base chemosensor for detection of Cu2+ and Ce4+ ions in aqueous media(Elsevier, 2025) Shahbaz, Muhammad; Sharif, Shahzad; Malik, Fouzia Perveen; Shah, Javed Hussain; Arooj, Anum; Sahin, Onur; Riaz, BilalA dual nature Schiff base chemosensor3,5-bis(((2-hydroxynaphthalen-1-yl)methylene)amino) benzoic acid (3,5-BHNMABA) was synthesized and characterized by single crystal X-rays diffraction. The interaction of the photophysical properties of the ligand with various metal ions (aqueous) was extensively analyzed through fluorescence spectrophotometry. EHOMO-ELUMO energy gap and molecular electrostatic potential study was performed by DFT calculations. Strong quenching in emission was observed for Cu2+ and Ce4+ ions. Binding ratio between Cu2+/Ce4+ ions with ligand was calculated by Job's plot. LOD and LOQ were calculated as 7.92 x 10-6 M and 2.40 x 10-5 M for Cu2+ ions whereas 5.9 x 10-6 M and 1.97 x 10-5 M for Ce4+ ions.Öğe Efficient Syntheses, Crystal Structure and Thermal Properties of Gabapentin 4-Acetamido, 2-Mesitylene and 2,4-Dinitro Sulfonamides Derivatives(Springer/Plenum Publishers, 2019) Kanwal, Nosheen; Khan, Islam Ullah; Sharif, Shahzad; Hussain, Erum Akbar; Mehmood, Arshad; Sahin, OnurEfficient syntheses of four derivatives G2-G5 of Gabapentin (G1) have been achieved. The structures of targeted compounds were investigated by elemental analysis, FT-IR, and H-1-NMR spectroscopic method. Crystal structures of G2 and G4 determined by single crystal X-ray diffraction method are also described. In G2 the molecules are stacked over each other in the form of layers and adjacent layers run parallel to each other. Intermolecular hydrogen bonding and van der Waals interactions are responsible for building the molecular assembly and packing of molecules in the unit. In G4, the molecules are arranged in parallel sheets formed by inter-molecular hydrogen bonds. The proposed synthetic route has high impact due to its simple reaction conditions of room temperature, water as a green solvent and short time to accomplish the reaction.Öğe Enhanced electrochemical performance of cerium-based metal organic frameworks derived from pyridine-2,4,6-tricarboxylic acid for energy storage devices(Elsevier, 2024) Shahbaz, Muhammad; Sharif, Shahzad; Shahzad, Ayesha; Sahin, Zarife Sibel; Riaz, Bilal; Shahzad, SundasModern era demands development of hybrid supercapacitor amalgamating characteristics of battery and supercapacitor is a single unit. Various contender electrode materials have been used so far, however, metal organic frameworks, having rich porosity and distinctive electrochemical properties can be integrated in energy storage devices to improve electrochemical performance. Herein, we have synthesized Ce-PTA-MOF from pyridine-2,4,6-tricarboxylic acid which was structurally as well as electrochemically characterized. Effects of different concentrations of KOH electrolyte on electrochemical properties of Ce-PTA-MOF electrode has been investigated using three electrodes assembly and practical applications of hybrid supercapacitor device has also been explored by fabricating it with activated carbon. The stability and capacitive-diffusive contributions of the hybrid supercapacitor has been analyzed by theoretical approach. The specific capacity, maximum energy density and power density were calculated as 115 C/g, 26.75 Wh/kg and 5760 W/kg respectively which showed efficiency of 99.2 % even after 5000 GCD cycles. High energy density and power density with extraordinary stability make Ce-PTA-MOF electrode a promising candidate for futuristic hybrid supercapacitor devices.Öğe Facile solvothermal syntheses of isostructural lanthanide(III) formates: Photocatalytic, photoluminescent chemosensing properties, and proficient precursors for metal oxide nanoparticles(Taylor & Francis Ltd, 2021) Farid, Sidra; Ameen, Saima; Sharif, Shahzad; Tariq, Madiha; Kundi, Israr Ahmad; Sahin, Onur; Sayyad, Muhammd HassanThree isostructural lanthanide coordination polymers (CPs) with the formula C(3)H(3)LnO(6) [Ln = Pr (1), Ce (2), and Dy (3)] were solvothermally synthesized by self-assembly of lanthanide(III) and in-situ generated methanoic acid by the hydrolysis of N,N-dimethyl formamide. These CPs were characterized by FTIR, elemental analysis, PXRD, and single crystal analysis. The metal centered luminescence properties of these coordination polymers revealed that only the dysprosium based CP exhibited significant luminescence, and it was found to be selective for chemosensing of picric acid. 3 showed quenching efficiency of 89.7% with K-SV value of 2.89 x 10(4) M-1. These coordination polymers were also exploited as photocatalysts for degradation of methylene blue, and the dysprosium based CP proved to be a fantastic photocatalyst with the degradation activity of 92% owing to its effective electronic transitions. The solvent-free thermolysis of these LnCPs fabricated CeO2 and Pr6O11 nanoparticles characterized by PXRD, FTIR, particle size analyzer, and elemental analysis.Öğe Hydrothermal synthesis, structural investigation, and magnetic properties of 2-D layered lanthanide (Ln = Pr, Eu, Gd, Tb, and Er) coordination polymers possessing infinite 1-D nanosized cavities(Taylor & Francis Ltd, 2015) Sharif, Shahzad; Sahin, Onur; Khan, Bushra; Khan, Islam UllahFive 2-D Ln(III) coordination polymers, [Ln(PDA)(PDAH)](n) (PDA=2,6-pyridinedicarboxylate), have been obtained under mild hydrothermal condition. In each coordination polymer, PDA is tetradentate and pentadentate, while lanthanides have coordination number eight to generate trigonal prismatic, triangular face bicapped LnO(6)N(2) geometry having 9 triangular and 2 square faces. Two different types of bridging oxygens are responsible to grow the 2-D coordination polymers providing open channels possessing infinite 1-D nanosized cavities. Adjacent 2-D chains are further extended to a 3-D hydrogen-bonded layered network through intermolecular - interactions and C-HO hydrogen bonds. Four lanthanides are arranged roughly at the vertices of a square and bridged by eight carboxylates leading to the overall tetrahedral shape of the secondary building units. The abnormal behavior of lanthanide contraction for the atomic radii of europium can be attributed to overlapping of electron clouds. The overall magnetic behavior is typical for the presence of antiferromagnetic exchange coupling interactions. Thermal decomposition analysis reveals that the coordination polymers have significant thermal stability. The coordination polymers are further characterized using elemental analysis and FT-IR spectroscopy.Öğe Improved electrochemical performance of nitrogen-containing copper-based 1D metal organic framework derived from highly connective pyridine-2,4,6-tricarboxylic acid for hybrid supercapacitors(Royal Soc Chemistry, 2025) Shahbaz, Muhammad; Sharif, Shahzad; Mushtaq, Muhammad Waheed; Ghaznazvi, Zainab; Iqbal, Zaeema; Khurshid, Muhammad Aqib; Sahin, OnurMetal organic frameworks (MOFs) are promising candidates for emergent energy storage devices due to their intrinsic properties, such as rich porosity, variable nano-geometries, and multifunctional characteristics. Here, we report the synthesis of copper-based MOFs (Cu-PTA-MOF), polyaniline (PANI), and polypyrrole (PPY), which have been characterized using different techniques. Pyridine-2,4,6-tricarboxylic acid (PTA) ligands were connected by metal ions through pi-d conjugated layers to generate the 1D polymer. Electrochemical attributes of Cu-PTA-MOF@AC, Cu-PTA-MOF@PANI and Cu-PTA-MOF@PPY were explored using a three-electrode assembly with 1 M KOH. Cu-PTA-MOF@PANI exhibited good results. For practical application, it was coupled with an activated carbon electrode in a hybrid supercapacitor device. The device exhibits a specific capacity of 232 C g-1, 72.5 W h kg-1 energy density and 4500 W kg-1 power density at 0.5 A g-1 current density with a coulombic efficiency of 98.8% even after 10 000 GCD cycles. The conductive polymer endowed the material with rapid ion and electron transfer and allowed utilization of the active material in a hybrid supercapacitor.Öğe Pyridine-2,6-Dicarboxylic Acid As a Facile and Highly Selective Turn-Off Fluorimetric Chemosensor for Detection of Cu (II) Ions in Aqueous Media(Springer/Plenum Publishers, 2024) Shah, Javed Hussain; Sharif, Shahzad; Shahbaz, Muhammad; Riaz, Bilal; Shahzad, Sundas; Sahin, Onur; Munawar, Khurram ShahzadCopper metal is third most abundant trace element in human body. Determination of Cu (II) ions is a burning topic in field of environment protection and food safety because of its significant impact on ecosystem. In this study, 2,6-pyridine dicarboxylic acid (PDA) has been explored as turn-off florescent probe for florescent detection of Cu (II) ions. This sensor showed highly selective complexing ability towards Cu (II) ions. Addition of aqueous solution of Cu (II) ions remarkably quenched the fluorescence intensity of PDA while, on contrary, there was no any prominent fluorescence quenching interference on addition of various metal ions. The binding mode of PDA and Cu (II) ions was determined as stoichiometry of 1:1 and it was further confirmed by single crystal XRD analysis. Mechanisms of static and dynamic quenching were confirmed by stern-volmer plot. Limit of detection (LOD) and limit of quantification (LOQ) for Cu (II) ions was calculated as 3.6 mu M and 1.23 mu M respectively, which is far below the acceptable value (31.5 mu M) according to the World Health Organization. The use of the sensor for detection of Cu (II) ions in real samples in aqueous media was also performed.Öğe Redox active cobalt based bi-linker metal organic frameworks derived from 5-sulfoisopthalic acid and 4,4-bipyridine for supercapacitor(Pergamon-Elsevier Science Ltd, 2025) Shah, Javed Hussain; Shahbaz, Muhammad; Sharif, Shahzad; Ullah, Ghulam; Shahzad, Sundas; Munawar, Khurram Shahzad; Sahin, OnurIn this research study, we have synthesized, characterized and extensively compared the electrochemical characteristics of two materials derived from 5-sulphoisophtalic acid, 4,4-bipyridine and cobalt metal using sonochemical method. Cobalt-bipyridine complex with 5-SIP in lattice structure (RG-41) showed predominant capacitive behavior whereas Co-SIP-Bpy MOF (RG-42) exhibited significant pseudocapacitive attributes due to the presence of coordination linkage responsible for the electron transfer. Due to the effective electrochemical properties of RG-42, we implemented it practically by fabricating a hybrid device with outstanding electrochemical features, demonstrating impressive 92 % cyclic stability with energy density and power density of 51.41 Wh/kg and 800 W/kg at 1 A/g, respectively. Dunn's method was employed to obtain capacitive-diffusive contributions for both half-electrochemical cells as well as hybrid device. These results underscored the potential of RG-42 as a competitive electrode material for future energy storage applications.Öğe Seven-, eight-, and ten-coordinated cerium(III) with highly connective pyridine-2,4,6-tricarboxylate, oxalate, and glycine ligands(Taylor & Francis Ltd, 2013) Khan, Islam Ullah; Sharif, Shahzad; Sahin, OnurTwo new 3-D Ce(III) coordination polymers, [Ce-1.3(PTA)(2)(Oxa)(2)(Gly)(H2O)(2)]center dot(Gly)4H(2)O (1) and [Ce-2.6(PTA)(4)(Oxa)(2)(H2O)(10)]center dot(MeOH)7H(2)O (2) (PTA=2,4,6-pyridinetricarboxylate, oxa=oxalate and Gly=glycine), were synthesized. The oxalate in 1 and 2, generated in situ from the cleavage and chemical rearrangement of PTAH(3), assembled into mixed-ligand networks to generate 3-D frameworks. Single crystal analysis reveals that in both complexes, Ce(III) shows coordination numbers of 7 and 10 in 1 and 8 and 10 in 2. PTA adopts four kinds of coordination modes. These complexes were further characterized using elemental analysis, FTIR spectroscopy and thermogravimetric analysis.Öğe Solvothermal synthesis, crystal structure, thermal, magnetic properties and DFT computations of a Ytterbium(III) complex derived from pyridine-2,6-dicarboxylic acid(Elsevier, 2022) Sharif, Shahzad; Saeed, Maham; Dege, Necmi; Bano, Rehana; Ahmad, Saeed; Gilani, Mazhar Amjad; Sahin, OnurA new ytterbium(III) complex, (DMAH(2))(3)[Yb(Pydc)(3)].4H(2)O (1) {Pydc = Pyridine-2,6-dicarboxylate anion, DMAH(2) = Dimethylammonium} has been prepared under mild solvothermal conditions and character-ized by elemental analysis, IR spectroscopy, thermal analysis and single crystal X-ray diffraction. The DMAH2 molecules in 1 , generated in situ from hydrolysis of N,N-dimethylformamide are responsible to assemble 2D coordination polymer through N-H center dot center dot center dot O and O-H center dot center dot center dot O h ydrogen bonding. Magnetic suscepti-bility measurements indicate that the complex ( 1 ) obeys the Curie Weiss law and the overall magnetic behavior is typical for the presence of weak antiferromagnetic exchange coupling interactions. Theoretical data for geometrical parameters of complex 1 agree well with the experimental data. Large HOMO-LUMO energy gap of 4.33 eV has provided kinetic stability to the complex 1 . NBO analysis reflects that in-tramolecular charge transfer occurred between ligand and metal orbitals with the highest stabilization energy of 1024.04 kcal/mol. The negative electrostatic potential at the nitrogen and dianionic pyridine-2,6-dicarboxylate regions confirms that these are dynamic locations for Yb(III) binding. (c) 2022 Elsevier B.V. All rights reserved.Öğe Structural, DFT and redox activity investigation of 2D silver based MOF for energy storage devices(Elsevier Science Sa, 2024) Sharif, Shahzad; Shah, Javed Hussain; Shahbaz, Muhammad; Riaz, Bilal; Shahzad, Sundas; Shahzad, Ayesha; Sahin, OnurA new silver(I) 2D MOF (Ag -MOF) was synthesized from 3,4-pyridinedicarboxylic acid (PDCA) by sonication method and characterized by single crystal X-ray diffraction, elemental analysis and FTIR spectroscopy. The material was further utilized for DFT computation and electrochemical performance. Theoretical and practical results for Ag -MOF geometrical parameters were found to be in reasonable agreement. Small HOMO-LUMO energy distance of 0.47 eV confirmed that electron transfer was much feasible. Distribution of electron isodensities was elaborated by DFT and FMOs computation. Double redox peaks in CV voltammograms reflected the change in oxidation state. Multiple plateaus in GCD curves showed the pseudo-capacitive behavior. Ag -MOF exhibited 101 Cg -1 specific capacity (Q s ), 123 Wh.kg - 1 energy density and 12,960 W kg -1 power density at current density of 5 Ag -1 . There was a small difference in R ct and R i which revealed that Ag -MOF had great ability to store energy. Presence of semi-circular arc in the EIS spectrum directly dictates the supercapacitor behavior. The electrode showed 97.5 % cyclic stability after 5000 cycles.Öğe Synthesis, Crystal Structure and Fluorimetric Study of 2-phenylphthalazin-1(2H)-one: a Highly Selective Florescent Chemosensor for Detection of Fe3+ and Fe2+ Metal Ions(Springer/Plenum Publishers, 2024) Sharif, Shahzad; Shahbaz, Muhammad; Sahin, Onur; Khurshid, Muhammad Aqib; Anbar, Maryam Musaffa; Dar, BirraA ligand, 2-phenylphthalazin-1(2H)-one (K), was synthesized by refluxing 2-formylbenzoic acid with phenyl hydrazine in presence of ethanol. FTIR, elemental analysis and single crystal XRD techniques were used to elucidate the structure. Fluorimetric turn-off response was recorded when solution of ligand (K) in DMF was treated with aqueous solution of Fe3+ and Fe2+ metal ions. No specific changes were observed on addition of other metal ions (Pb2+, Cd2+, Mn2+, Zn2+, Ba2+, Ni2+, Al3+, Ag1+, Co2+, Ca2+, Cu2+, Mg2+, Cr3+). Limit of Detection (LOD) was calculated for Fe-2 and Fe(3+)as 2.4 mu M and 2.5 mu M respectively, which is quite below to the recommended value 5.4 mu M of the Environment Protection Agency of USA. Association constants for Fe3+ and Fe2+ metal ions were determined as 6x10(-4) M-1 and 3.6x10(-4) M-1 respectively. Benesi-Hildebrand plot confirmed 1:1 binding ratio between metal ions and ligand.Öğe Synthesis, crystal structure and magnetic properties of an octanuclear cerium(III) complex of pyridine-2,6-dicarboxylate(Walter De Gruyter Gmbh, 2019) Sharif, Shahzad; Khan, Islam Ullah; Sahin, Onur; Jabeen, Nadia; Ahmad, Saeed; Khan, BushraAn octanuclear compound of cerium(III), [Ce-8(Pydc)(10)(HPydc)(4)center dot 22H(2)O]center dot 11H(2)O (1) (Pydc = pyridine-2,6-dicarboxylate anion) was prepared under mild solvothermal conditions and its crystal structure was determined by single-crystal X-ray diffraction. Three kinds of coordination environments are observed, which include: [Ce(Pydc)(3)], [Ce(Pydc)(H2O)(4)(O,O)], and [Ce(H2O)(7) (O,O)]. Each cerium atom in 1 is nine-coordinated but two different geometries are found. The Ce1 and Ce2 atoms exhibit a nearly tricapped trigonal prismatic CeN3O8 geometry, while Ce3 and Ce4 possess CeNO8 and CeO9 coordination polyhedra, which approximate to slightly distorted mono-capped square antiprisms having 12 triangular faces. The Pydc ligands adopt tri-, tetra-, and penta-coordination modes through tridentate chelating and, mu(2) and mu(3)-bridging modes, respectively. The clusters are joined by O-II center dot center dot center dot O hydrogen bonds to generate 3D supramolecular network. Magnetic susceptibility measurements for 1 indicate that the chi(m) values obey the Curie-Weiss law. The overall magnetic behavior is typical for the presence of antiferromagnetic exchange coupling interactions between the cerium(III) ions.Öğe Ultrasonic assisted synthesis of Zn(II) 2D coordination polymer and 4-nitroaniline photoluminescence sensing manifestation through DFT studies(Taylor & Francis Ltd, 2022) Riasat, Madiha; Sharif, Shahzad; Khurshid, Shazia; Farid, Sidra; Bano, Rehana; Gilani, Mazhar Amjad; Sahin, OnurZinc(II) 2 D polymer, [Zn(3,5-Pydc)(0.5)center dot H2O](n) (1) {3,5-Pydc = pyridine-3,5-dicarboxylate anion}, has been prepared under sonication conditions. The natural bond orbital (NBO) analysis revealed that charge transfer transitions in the vicinity of Zn(II) is accompanied with the highest stabilization energy of 140.13 kcal/mol. Furthermore, molecular electrostatic potential (MEP) analysis has been carried out to identify the reactive sites over the surface of the complex. 1 was characterized by elemental analysis, FTIR spectroscopy, thermal analysis and single crystal X-ray diffraction. The metal-based luminescence properties revealed that 1 can be used as selective chemosensor against 4-nitroaniline. Complex 1 showed excellent quenching efficiency of 98.9% with K-SV value of 3.7 x 10(5) M-1. Density functional theory simulations complement to the specific luminescence quenching of 1 against 4-nitroaniline.
