Yazar "Shah, Javed Hussain" seçeneğine göre listele

Listeleniyor 1 - 7 / 7
  • [ X ]
    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, 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.
  • [ X ]
    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, 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.
  • [ X ]
    Öğe
    Nitrogen and sulfur-rich cobalt complex for hybrid supercapacitor applications
    (Elsevier, 2025) Saeed, Maham; Shah, Javed Hussain; Sharif, Shahzad; Shahbaz, Muhammad; Ullah, Ghulam; Shahzad, Ayesha; Sahin, Zarife Sibel
    In the quest for more effective and advanced energy storage devices, an integrated methodology combining both battery and supercapacitor hybrid features is being explored. In this regard, we have developed a cobalt-1,10-phenonthroline complex with 5-sulfoisopthalic acid in the lattice (Co-Phen@SIP) via sonication method. Structural properties were explored by Single-crystal XRD, Elemental analysis, TGA, FTIR, UV Visible and Fluorescence spectroscopy while detailed electrochemical study was carried out via CV, GCD and EIS. Three electrode setup revealed pseudocapacitive properties of Co-Phen@SIP with specific capacity of 157.6 Cg(-1) at 2 A g(-1). Battery-supercapacitor hybrid device showed energy density and power density of 13.03 Wh kg(-1) and 3309 W kg(-1) respectively. The device also exhibited remarkable columbic efficiency of 98.94 % even after 5000 GCD cycles. Theoretical approach based on Dunn's model and power law was also applied to check the capacitivediffusive contributions of three-electrode system and hybrid device. 1, 10-phenonthroline induces structural stability over long cyclability. The introduction of SIP in Co-complex caused charge transfer through pi center dot center dot center dot pi interactions providing porous and robust structure which aided in improved electric conductivity and ionic mobility. This multi-ligand chemistry with the redox active cobalt has achieved superior performance and reversibility in comparison to other traditional complexes. The idea came out to be an effective strategy for advanced hybrid supercapacitors.
  • [ X ]
    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 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.
  • [ X ]
    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, 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.
  • [ X ]
    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, 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.
  • [ X ]
    Öğe
    Synergetic interplay of a nitrogen- and sulfur-rich copper bi-linker 2D cubic-layered MOF composite with MXene for improved hybrid supercapacitor application
    (Royal Soc Chemistry, 2025) Saeed, Maham; Sharif, Shahzad; Shah, Javed Hussain; Afzal, Tayyaba Tur Rehman; Shahbaz, Muhammad; Shehzad, Azhar Mehmood; Shahzad, Ayesha
    To combine the properties of batteries and capacitors in a single hybrid device, metal-organic frameworks have emerged as promising materials. In this study, by incorporation of a heteroatom (N, O and S)-based bi-linker, a novel copper-based two-dimensional metal-organic framework (Cu-SIP-MOF), derived from 5-sulfoisophathalic acid monosodium salt (SIP sodium salt) and 4,4-bipyridine was synthesized and characterized using different techniques. The conductivity of the extended 2D MOF was attributed to pi-d orbital contribution, which was further enhanced by fabricating its composite with MXene. The synthesized MOFs and its composites were electrochemically evaluated using different electroanalytical techniques such as cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy via three-electrode assembly. The composites of Cu-SIP-MOF with MXene (CM-200) in a 1 : 2 ratio possessed the highest specific capacity of 683.69 C g-1, highlighting the potential for their practical implementation in asymmetric hybrid devices. The material demonstrated an energy density and a power density of 62 W h kg-1 and 2330.4 W kg-1, respectively. It also expressed 98.3% coulombic efficiency after 5000 galvanic charge-discharge cycles. The significant values of specific capacity, energy density and power density of CM-200 make it a promising electrode material for a futuristic hybrid device.