Yazar "Shahbaz, Muhammad" seçeneğine göre listele

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    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, Saeed
    A 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.
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    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, Bilal
    A 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.
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    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, Sundas
    Modern 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.
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    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, Onur
    Metal 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.
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    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 Shahzad
    Copper 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.
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    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, Onur
    In 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.
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    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, Onur
    A 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.
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    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, Birra
    A 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.