Controlled synthesis and growth mechanism of zinc cobalt sulfide rods on Ni-foam for high-performance supercapacitors

Iftikhar Hussain,Charmaine Lamiel,Saad Gomaa Mohamed,수부칼라이비자야쿠마르,Awais Ali,심재진 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.71 No.-

Rod-like zinc cobalt sulfide (ZCS) with controlled uniform structure was synthesized using a single-stephydrothermal method and its growth mechanism was investigated. A ZCS-based electrode showed anultrahigh capacitance of 2,418 F g 1 (967 C g 1) at 1 A g 1 with a good cycling stability of 83% after 10,000cycles. Moreover, an asymmetric ZCS-12//activated carbon supercapacitor, exhibited a high capacitanceof 142 F g 1 (227 C g 1) at 0.5 A g 1 and a high energy density of 51 Wh kg 1 and a high power density of8 kW kg 1, highlighting the next generation high performance supercapacitors.

A 3D walking palm-like core-shell CoMoO₄@NiCo₂S₄@nickel foam composite for high-performance supercapacitors

Hussain, Iftikhar,Ali, Awais,Lamiel, Charmaine,Mohamed, Saad Gomaa,Sahoo, Sumanta,Shim, Jae-Jin The Royal Society of Chemistry 2019 Dalton Transactions Vol.48 No.12

<P>Supercapacitors are one of the most promising renewable-energy storage systems. In this study, a three-dimensional walking palm-like core-shell CoMoO4@NiCo2S4@nickel foam (NF) nanostructure was synthesized using a two-step hydrothermal method for high electrochemical performance. The as-prepared composite exhibited a high areal capacitance of 17.0 F cm<SUP>−2</SUP> (2433 F g<SUP>−1</SUP>) at a current density of 5 mA cm<SUP>−2</SUP> in a three-electrode system. The results revealed outstanding cycling stability of 114% after 10 000 charge-discharge cycles. An aqueous asymmetric supercapacitor device assembled with CoMoO4@NiCo2S4@NF and activated carbon (AC)@NF as the positive and negative electrodes, respectively, showed a high capacitance of 4.19 F cm<SUP>−2</SUP> (182 F g<SUP>−1</SUP>) and delivered a high energy density of 60.2 W h kg<SUP>−1</SUP> at a power density of 188 W kg<SUP>−1</SUP> and a high power density of 1.5 kW kg<SUP>−1</SUP> at an energy density 29.2 W h kg<SUP>−1</SUP>, lighting 22 parallel-connected red light emitting diodes for over 60 s. The synergistic effects of the core-shell CoMoO4@NiCo2S4@NF electrode material highlight the potential of this composite as an effective active material for supercapacitor applications.</P>

Genome-wide identification and comparative analysis of MATE gene family in Cucurbitaceae species and their regulatory role in melon (Cucumis melo) under salt stress

Shah Iftikhar Hussain,Manzoor Muhammad Aamir,Sabir Irfan Ali,Ashraf Muhammad,Haq Fazal,Arif Samiah,Abdullah Muhammad,Niu Qingliang,Zhang Yidong 한국원예학회 2022 Horticulture, Environment, and Biotechnology Vol.63 No.4

The multidrug and toxic compound extrusion (MATE) protein family includes a primeval gene family of secondary transporters that export toxins, extrude metabolites, and participate in plant defense mechanisms. However, lack of information regarding the MATE gene family in Cucurbitaceae, a comprehensive genome-wide analysis of the MATE family was carried out in four Cucurbitaceae species (Cucumis melo, Cucumis sativus, Cucurbita pepo, and Lagenaria siceraria), and 174 MATE genes were identified. Phylogenetic and structural analysis revealed that the Cucurbitaceae MATE transporters family could be further classified into seven subgroups (A–G). GO annotation-based subcellular localization analysis predicted that most of the MATE gene family members localized on the plasma membrane. Moreover, conserved motifs and gene structure (intron/exon) analysis revealed the functional divergence between clades. Transposed duplication events have played a key role in the expansion and evolution of the MATE gene family in Cucumis melo. Cis-acting elements analysis of MATE family genes revealed that these could be targeted by a diverse set of trans-acting factors involving the MATE gene family to manage diverse stress conditions. The Chromosomal localization and molecular characteristics (weight, length, and pI) were performed using numerous bioinformatics tools. Intraspecies microsynteny analysis demonstrated that maximum orthologous genes were found between A. thaliana, C. pepo, C. lanatus, and L. siceraria. Further, functional analysis of microRNAs demonstrated miRNAs are involved in the growth and regulation of MATE genes. Finally, eleven candidates MATE genes were selected randomly, and their expression analysis was carried out via qRT-PCR at 0 h and after 24 h of salt stress. Furthermore, transient CmMATE expression in Arabidopsis thaliana protoplasts showed that protein localized on the plasma membrane. This study provides insights into the functional analysis of the MATE gene family in Cucurbitaceae species and laid down the basic knowledge to explore the role and mechanism of the MATE gene family to cope with severe salt stress conditions.

Improved photocatalytic degradation efficiency of methylene blue via MgAl2O4–graphene nanocomposite

Ali Ahmed,Gul Iftikhar Hussain,Khan Muhammad Zarrar,Javaid Farhan 한국세라믹학회 2023 한국세라믹학회지 Vol.60 No.2

In the present work, Magnesium Aluminate (MgAl2O4) nanoparticles and MgAl2O4–graphene nanocomposites with various graphene weight percentages (1, 2, 3, 4, and 5%) were prepared via sol–gel and ultra-sonication methods, respectively. The formation of the spinel phase was confirmed through XRD analysis. Scanning Electron Microscopy was used to study the morphology of the MgAl2O4 nanoparticles and their anchoring on the graphene sheets. The FTIR analysis also confirmed the presence of tetrahedral and octahedral bands at 695 and 526 cm−1, respectively. For magnesium aluminate nanoparticles, the bandgap was calculated to be 5.4 eV, which decreases to 4.9 eV with 5% graphene loading on the MgAl2O4–graphene nanocomposites. For methylene blue dye, the degradation efficiency of the 5% MgAl2O4–graphene nanocomposites was also found to be higher (90%) as compared to the pristine MgAl2O4 nanoparticles (70%). This increase in efficiency depicts their enhanced photocatalytic activity and strongly suggests that the MgAl2O4–graphene nanocomposites could be a good candidate for industrial wastewater remediation.

One-step synthesis of hollow C-NiCo₂S₄ nanostructures for high-performance supercapacitor electrodes

Mohamed, Saad Gomaa,Hussain, Iftikhar,Shim, Jae-Jin Royal Society of Chemistry 2018 Nanoscale Vol.10 No.14

<P>Carbon-containing NiCo2S4 hollow-nanoflake structures were fabricated by a one-step solvothermal method using CS2 as a single source for sulfidation and carbonization. The reaction mechanism for the hollow structure with carbon residues was explored based on the formation of a bis(dithiocarbamate)-metal complex and the Kirkendall effect during solvothermal synthesis. The NiCo2S4 nanoflake electrode exhibited a high specific capacitance of 1722 F g<SUP>−1</SUP> (specific capacity 688.8 C g<SUP>−1</SUP>) at a current density of 1 A g<SUP>−1</SUP> and an excellent cycling stability (capacity retention of 98.8% after 10 000 cycles). The as-fabricated asymmetric supercapacitor based on NiCo2S4 nanoflakes and activated carbon electrodes revealed a high energy density of 38.3 W h kg<SUP>−1</SUP> and a high power density of 8.0 kW kg<SUP>−1</SUP> with a capacitance retention of 91.5% and a coulombic efficiency of 95.6% after 5000 cycles, highlighting its great potential for practical supercapacitor applications.</P>

Stiff, Strong, Yet Tough Free-Standing Dielectric Films of Graphene Nanosheets-Polyurethane Nanocomposites with Very High Dielectric Constant and Loss

Rahim Jan,AMIR HABIB,Iftikhar Hussain Gul 대한금속·재료학회 2016 ELECTRONIC MATERIALS LETTERS Vol.12 No.1

In this study, graphene nanosheets (GNS) prepared through a liquid exfoliationtechnique are dispersed in thermoplastic polyurethane (TPU) at a volume fraction(Vf) of up to 0.19. Then, the electrical and mechanical properties of the obtainedcomposites are characterized. The dielectric spectroscopy shows an excessivevariation in dielectric constant (1.1 to 3.53 × 107) and dielectric tangent loss (0.03to 2515) with varying Vf over the frequency range of 25 kHz to 5 MHz. Aconsiderable enhancement in electrical conductivity (DC) is found, from3.87 × 10−10 S/m (base polymer) to 53.5 S/m for the 0.19 Vf GNS-TPUnanocomposite. The GNS-TPU composites are mechanically robust, with aconsiderable increase in stiffness (~4-fold) and strength (almost twice),maintaining its ductility up to 0.09 Vf GNS. The high dielectric constant at lowerfrequencies is attributed to the well-established Maxwell-Wagner polarizationeffect, whereas the high dielectric tangent loss is due to leakage currents as aphysical conducting network is formed at high filler loadings. The layeredstructure, high aspect ratio, and improved dispersion of GNS are the main reasonsfor the improvement in both the dielectric characteristics and the mechanicalproperties of the host polymer.

Ce-Substituted Co0.5Ni0.5Fe2O4: Structural, Morphological, Electrical, and Dielectric Properties

Syed Samar Abbas,Iftikhar Hussain Gul,Shahid Ameer,Muhammad Anees 대한금속·재료학회 2015 ELECTRONIC MATERIALS LETTERS Vol.11 No.1

Functional nano ceramics, especially rare earth substituted ferrites, havenumerous applications in microelectronics. They have certain novelcharacteristics associated with various rare earth substitutions associatedwith electronics. A series of cerium-substituted cobalt nickel ferritenanoparticles with nominal composition CexCo0.5Ni0.5Fe2-xO4 (wherex = 0.00, 0.05, 0.10, 0.15, and 0.20) was prepared in powder form bychemical co-precipitation and sol-gel auto combustion methods. Sampleswere characterized by x-ray diffraction (XRD), scanning electronmicroscopy (SEM), Fourier transform infrared spectroscopy (FT-IR),dielectric properties, and DC electrical resistivity. XRD analysis of all thesamples confirms the formation of the spinel structure of Fd-3m spacegroup. Crystallite size “t” was found to decrease, whereas both x-raydensity “Dx” and lattice constant “a” were found to increase by increasingCe concentration from 8.35 Å to 8.36 Å and 8.37 Å for sol-gel and coprecipitation,respectively. SEM results show the presence of uniformlydistributed and almost spherical-shaped particles for both techniques. FTIR measurements were used to further confirm thecomposition, i.e., cation substitution. The DC electrical resistivity of the x = 0.00 sample is higher than Ce-substituted ferritesamples and in the range of 108 Ω-cm at 373 K. Dielectric spectroscopy is also studied from 100 Hz to 5 MHz as a function offrequency. To our knowledge, this is the first reported research of this particular composition.

Blends of polyurethane-polymethyl methacrylate/TiO2-based composites

Mohammad Zuber,Shazia Tabasum,Rizwan Hussain,Muhammad Bilal Khan,Iftikhar Hussain Bukhari 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.8

Polyurethanes (PUs) prepolymer was prepared by the reaction of toluene-2,4-diisocyanate (TDI) and poly caprolactone diols and the chain was further extended with 1,4-butane diol (1,4-BDO) to get final polyurethane (PU). FTIR spectra of the monomers, PU prepolymer, chain extender and final PU confirmed the reaction progress. A series of blends were prepared by varying the percent compositions of prepared PU, procured polymethyl methacylates (PMMA)and titanium dioxide (TiO2). Pellets were formed from the prepared blends (PU-PMMA/TiO2) using a self-designed mechanical tool. Scanning electron microscope (SEM) images were also taken to confirm the incorporation of the TiO2contents into the prepared blends. Mechanical properties such as hardness and compressive strength were studied and discussed. The results of the study reveal that the blended sample having 80% PU, 20% PMMA content with 2.5 g TiO2 in 100 g mixture of PU and PMMA is very suitable for suggesting dental materials.

Enhancement of electrochemical performance of nickel cobalt layered double hydroxide@nickel foam with potassium ferricyanide auxiliary electrolyte

Lamiel, Charmaine,Nguyen, Van Hoa,Hussain, Iftikhar,Shim, Jae-Jin Elsevier 2017 ENERGY Vol.140 No.1

<P><B>Abstract</B></P> <P>Metal oxide nanostructures have been studied widely to overcome the limitations in the capacitance of the carbon-based supercapacitor electrode materials. An electrode with a very porous 3D structure is preferred to facilitate the mass transfer of large electrolyte ions. In this study, highly nanostructured, binder-free Ni-Co-based pseudocapacitive electrodes were synthesized directly on porous 3D structured nickel foam (NF) current collectors using low-power microwave irradiation. The electrochemical performance of the Ni-Co layered double hydroxide (Ni-Co-LDH) showed better performance than Ni-Co oxide (Ni-Co-O) with the further addition of redox additive/active electrolytes, such as K<SUB>3</SUB>Fe(CN)<SUB>6</SUB>. The specific capacitances of 4664 F g<SUP>−1</SUP> for Ni-Co-LDH and 1758 F g<SUP>−1</SUP> for Ni-Co-O at 5 mA cm<SUP>−2</SUP> in the KOH/K<SUB>3</SUB>Fe(CN)<SUB>6</SUB> electrolyte were improved greatly compared to the values of their corresponding materials in the conventional KOH electrolyte (2875 and 250 F g<SUP>−1</SUP>, respectively). Interestingly, the Ni-Co-LDH//AC asymmetric device exhibited a specific capacitance of 108.9 F g<SUP>−1</SUP> and an energy density of 38.7 Wh kg<SUP>−1</SUP> with a stability of 61.9% after 5000 cycles. The facile yet cost-effective synthesis of nanostructured electrodes provides a versatile approach for the design of high-performance pseudocapacitive electrodes for future energy-storage systems.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Binder-free 3D Ni-Co LDH nanoflakes on Ni foam were synthesized under microwave. </LI> <LI> Ni-Co-LDH had a high specific capacitance 2875 F g<SUP>−1</SUP>, while Ni-Co-O had 250 F g<SUP>−1</SUP>. </LI> <LI> The Specific capacitance increased from 2875 to 4664 F g<SUP>−1</SUP> by adding K<SUB>3</SUB>Fe(CN)<SUB>6</SUB>. </LI> <LI> 91.1% of capacitance of Ni-Co-LDH was retained after 3000 cycles in KOH/K<SUB>3</SUB>Fe(CN)<SUB>6</SUB>. </LI> <LI> The Ni-Co-LDH//AC asymmetric device showed an energy density of 38.7 Wh kg<SUP>−1</SUP>. </LI> </UL> </P>

Removal of lead and cobalt using lignocellulosic fiber derived from Citrus reticulata waste biomass

Haq Nawaz Bhatti,Iqra Ijaz Bajwa,Muhammad Asif Hanif,Iftikhar Hussain Bukhari 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.1

The present investigation explored the use of Citrus reticulata waste biomass (CWB) for the removal of Pb(II) and Co(II) from the aqueous solutions. The Pb(II) and Co(II) biosorption was found to be dependent on pH of the solution, biosorbent dose, biosorbent particle size, temperature, shaking speed, contact time and initial concentration of metal ions. A metal uptake capacity of 41.16 and 52.64 mg/g was observed at pH 5 and 7 for Pb(II) and Co(II),respectively. The biosorption data followed the Freundlich model for both metals. The overall biosorption process was best described by pseudo-second order kinetics. The effect of several pretreatments on the biosorption efficiency of CWB was also investigated. The results demonstrated that pretreatments influenced the biosorption capacity of the biomass for the both metals significantly. Maximum biosorption capacity of 83.77 and 95.55 mg/g was observed for Pb(II) and Co(II) with sodium hydroxide treated and simply heated biomass, respectively. FTIR spectrum indicated the presence of -OH, -NH, -COOH groups in the biomass. The surface structure of CWB was analyzed by JEOL JMT 300 scanning electron microscope (SEM), and the existence of metal ions on the surface of biosorbent was determined by energy dispersive X-ray (EDX) spectroscopy.