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Flexible and mechanically durable asymmetric supercapacitor based on nico-layered double hydroxide and nitrogen-doped graphene using a simple fabrication method
, Article Energy Technology ; Volume 7, Issue 5 , 2019 ; 21944288 (ISSN) ; Gilshteyn, E. P ; Melandsø Buan, M. E ; Sorsa, O ; Jiang, H ; Iraji zad, A ; Shahrokhian, S ; Nasibulin, A. G ; Kallio, T ; Sharif University of Technology
Wiley-VCH Verlag
2019
Abstract
A high-performing, lightweight, and flexible asymmetric supercapacitor (ASC) using NiCo-layered double hydroxide (NiCo LDH) supported on 3D nitrogen-doped graphene (NG) as a positive electrode and NG as a negative electrode is demonstrated. Highly conductive NG provides fast electron transfer and facilitates (dis)charging of NiCo LDH deposited on it. The composite electrode of NiCo LDH@NG exhibits a high specific capacitance of 1421 F g −1 at 2 A g −1 . Moreover, the as-obtained hybrid electrode shows an excellent rate capability with a specific capacitance of 1397 F g −1 at a high current density of 10 A g −1 , which is about 98% of the capacitance obtained at 2 A g −1 . The flexible ASC...
First heterobimetallic AgI–CoIII coordination compound with both bridging and terminal –NO2 coordination modes: Synthesis, characterization, structural and computational studies of (PPh3)2AgI– (μ-κ2O,O′:κN-NO2)–COIII(DMGH)2(κN-NO2)
, Article Acta Crystallographica Section C: Structural Chemistry ; Volume 74, Issue 8 , 2018 , Pages 882-888 ; 20532296 (ISSN) ; Batmanghelich, S ; Raithby, P. R ; Sharif University of Technology
Wiley-Blackwell
2018
Abstract
An unusual heterobimetallic bis(triphenylphosphane)(NO2)AgI–CoIII(dimethyl-glyoximate)(NO2) coordination compound with both bridging and terminal –NO2 (nitro) coordination modes has been isolated and characterized from the reaction of [CoCl(DMGH)2(PPh3)] (DMGH2 is dimethylglyoxime or N,N′-di-hydroxybutane-2,3-diimine) with excess AgNO2. In the title compound, namely bis(dimethylglyoximato-1κ2O,O′)(μ-nitro-1κN:2κ2O,O′)(nitro-1κN)bis(triphenyl-phosphane-2κP)cobalt(III)silver(I), [AgCo(C4H7N2O2)2(NO2)2(C18H15P)2], one of the ambidentate –NO2 ligands, in a bridging mode, chelates the AgI atom in an isobidentate κ2O,O′-manner and its N atom is coordinated to the CoIII atom. The other –NO2 ligand...
Tailoring of structural, dielectric, and magnetic properties of SrBaCu2Fe12O22 hexaferrites by doping with Gd–Co binary mixtures
, Article Applied Physics A: Materials Science and Processing ; Volume 128, Issue 9 , 2022 ; 09478396 (ISSN) ; Khan, M. A ; Akhtar, M. N ; Gulbadan, S ; Ejaz, S. R ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Gadolinium (Gd) and cobalt (Co) substituted Sr–Ba–Cu-based Y-type hexaferrites were synthesized with the help of the sol–gel auto-combustion route. XRD (X-ray diffraction) analysis was done to ratify the phase formation of hexaferrites. The impact of Gd3+ substitutions was measured on all the lattice parameters. Lattice constants “a” and “c” were found between 5.879–5.891 Å and 43.185–43.620 Å, respectively. It was observed from the XRD analysis that with an increase in Gd–Co contents, the enhancement in the average crystallite size is noted. The thermal decomposition process was studied using TGA (thermogravimetric analysis), revealing that the precursor may give the ending product when...
Influence of vanadium, cobalt-codoping on electrochemical performance of titanium dioxide bronze nanobelts used as lithium ion battery anodes
, Article Journal of Materials Science: Materials in Electronics ; 2018 , Pages 1-9 ; 09574522 (ISSN) ; Askari, M ; Sharif University of Technology
Springer New York LLC
2018
Abstract
In this work, V, Co-codoped TiO2(B) samples are synthesized through a hydrothermal method, and used as negative electrode materials for lithium ion batteries. The amount of dopants is varied in order to investigate their influence on electrochemical properties. The formation of V, Co-codoped TiO2(B) nanobelts with widths of 20 and 60 nm is demonstrated using X-ray diffraction, X-ray photoelectron spectroscopy, inductively coupled plasma–optical emission spectrometry and field-emission scanning electron microscopy analyses. In addition, the electrochemical properties of the samples are tested by cyclic voltammetry, charging/discharging, and cyclic performance techniques. Compared to other...
Property Investigation of Poly (Ethylene Co-vinyl Acetate)/Poly (l-Lactic Acid)/Organo Clay Nanocomposites
, Article Journal of Polymers and the Environment ; Volume 27, Issue 12 , 2019 , Pages 2886-2894 ; 15662543 (ISSN) ; Ramazani SaadatAbadi, A ; Sharif University of Technology
Springer New York LLC
2019
Abstract
In this study, EVAc/PLA/organo clay nanocomposites were prepared via solution mixing method. The SEM images were used to investigate the morphology of nanocomposites revealing no phase separation or agglomeration of disperse phase in EVAc/PLA blends and nanocomposites. SAXS spectra confirmed the intercalated morphology of nanocomposites. Soil burial test were carried out and the rate of degradation of the samples were measured indirectly. Oxygen gas permeability of EVAc was slightly decreased by adding PLA to the matrix, when small loads of clay caused dramatic improvement in barrier properties. Melt rheological frequency sweep test illustrated the compatibility of EVAc with low contents of...
Co-doping a metal (Cr, Mn, Fe, Co, Ni, Cu, and Zn) on Mn/ZSM-5 catalyst and its effect on the catalytic reduction of nitrogen oxides with ammonia
, Article Research on Chemical Intermediates ; Volume 43, Issue 4 , 2017 , Pages 2143-2157 ; 09226168 (ISSN) ; Hamidzadeh, M ; Sharif University of Technology
Springer Netherlands
2017
Abstract
Selective catalytic reduction (SCR) of NOx by NH3 over a series of Mn–M/Z catalysts (M = Cr, Mn, Fe, Co, Ni, Cu, Zn, and Z = the ZSM-5 Zeolite) synthesized by wet impregnation method was investigated. Mn–Fe/Z, Mn–Co/Z, and Mn–Cu/Z catalysts exhibited approximately 100 % NOx conversion over a wide temperature range (200–360 °C) in a defined atmospheric condition, which was noticeably greater than that of Mn–Cr/Z (340–360 °C). Furthermore, the effect of addition of second metal oxide species to the initial Mn/Z catalyst on the structure of catalysts was studied by several characterization techniques. BET measurements revealed high surface area and pore volume of the Mn–Cu/Z catalyst. In...
Statistical, morphological, and corrosion behavior of PECVD derived cobalt oxide thin films
, Article Journal of Materials Science: Materials in Electronics ; Volume 30, Issue 24 , 2019 , Pages 21185-21198 ; 09574522 (ISSN) ; Alam, M. H ; Dastan, D ; Ziakhodadadian, S ; Shi, Z ; Garmestani, H ; Weidenbach, A. S ; Ţălu, Ş ; Sharif University of Technology
Springer
2019
Abstract
Experimental parameters have direct influences on materials properties and therefore their applications. The effect of plasma power on the properties of cobalt oxide thin films, prepared using plasma-enhanced chemical vapor deposition technique, on stainless steel substrates have been addressed in this paper. The structural, morphological, and compositional properties of these films were investigated by means of X-ray diffraction (XRD), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS) technique. The XRD patterns demonstrated the growth of polycrystalline Co3O4 thin film with a cubic spinel structure such that the intensity of (511) and (311) peaks increase as the...
Wettability and rheological behavior of low Ag lead-free SAC/graphene and cobalt-graphene nanocomposite solder paste
, Article Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science ; Volume 53, Issue 8 , 2022 , Pages 2811-2822 ; 10735623 (ISSN) ; Movahedi, M ; Kokabi, A. H ; Miyashita, Y ; Azghandi Rad, S ; Sharif University of Technology
Springer
2022
Abstract
The impacts of dopant nanoparticles, graphene nanosheets (GNSs) and cobalt decorated-graphene nanosheets (CoGNSs), were studied in relation to the wettability and rheological behavior in low-Ag lead-free SAC0307 (Sn–0.3Ag–0.7Cu) solder paste. The solidification range of the solders was evaluated using differential scanning calorimetry. Phase identification in the solder bulk and interface of the solder and copper substrate was carried out by X-ray diffraction and energy-dispersive X-ray spectroscopy. Spreading properties and reactive wetting behavior along with the rheological properties of the solders were also studied. Results showed that the addition of both nanoparticles did not...
3D flower-like binary nickel cobalt oxide decorated coiled carbon nanotubes directly grown on nickel nanocones and binder-free hydrothermal carbons for advanced asymmetric supercapacitors
, Article Nanoscale ; Volume 11, Issue 6 , 2019 , Pages 2901-2915 ; 20403364 (ISSN) ; Shahrokhian, S ; Rahimi, S ; Sharif University of Technology
Royal Society of Chemistry
2019
Abstract
The development of high performance supercapacitors with high energy densities without sacrificing power densities has always been at the leading edge of the emerging field of renewable energy. Herein, the design and fabrication of innovative high performance binder-free electrodes consisting of coiled carbon nanotubes (CNTs) and biomass-derived hydrothermal carbon spheres (HTCSs) as, respectively, positive and negative electrodes is reported. High performance asymmetric supercapacitors (ASCs) were developed using novel 3D core/shell-like binary Ni-Co oxide (NCO) decorated coiled CNTs directly grown on Ni nano-cone arrays (NCAs) and HTCSs directly deposited on NCAs. Novel 3D structures of...
Biomass-derived wearable energy storage systems based on poplar tree-cotton fibers coupled with binary nickel-cobalt nanostructures
, Article Sustainable Energy and Fuels ; Volume 4, Issue 2 , 2020 , Pages 643-654 ; Unalan, H. E ; Shahrokhian, S ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
We hereby demonstrate symmetric and asymmetric supercapacitors (SSCs and ASCs) based on core/shell-like Ni-Co oxide@cotton//Fe2O3-carbon nanotubes@cotton that are capable of storing a remarkable amount of energy, while retaining a high power density and long cycle life. Hierarchical, porous structures of Ni-Co-O nano-rod (NR) decorated Pd-activated cotton fibers (CFs) were fabricated using an eco-benign hydrothermal method and directly used as the cathode of the supercapacitors. Fe2O3-single-wall carbon nanotube (SWCNT) decorated CFs were employed as anodes of the fabricated ASCs. The assembled Ni-Co-O@cotton//Fe2O3-SWCNTs@cotton based ASCs possessed the benefits of a relatively high energy...
3D ternary Ni: XCo2- xP/C nanoflower/nanourchin arrays grown on HCNs: A highly efficient bi-functional electrocatalyst for boosting hydrogen production via the urea electro-oxidation reaction
, Article Nanoscale ; Volume 12, Issue 30 , 2020 , Pages 16123-16135 ; Shahrokhian, S ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Over the last few years, substantial efforts have been made to develop earth-abundant bi-functional catalysts for urea oxidation and energy-saving electrolytic hydrogen production due to their low cost and the potential to replace traditional noble-metal-based catalysts. Nevertheless, finding a straightforward and effective route to prepare efficient catalysts with unique structural features and optimal supports still is a big challenge. Among the various candidates, metal-organic framework (MOF)-derived materials show great advantages as new kinds of active non-precious catalysts. On the other hand, the controllable integration of MOFs and carbon-based nanomaterials leads to further...
Dual-electrocatalysis behavior of star-like zinc-cobalt-sulfide decorated with cobalt-molybdenum-phosphide in hydrogen and oxygen evolution reactions
, Article Nanoscale ; Volume 13, Issue 41 , 2021 , Pages 17576-17591 ; 20403364 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Royal Society of Chemistry
2021
Abstract
Although important advances have been acquired in the field of electrocatalysis, the design and fabrication of highly efficient and stable non-noble earth-abundant metal catalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) remain a significant challenge. In this study, we have designed a superior bifunctional catalyst for OER and HER in alkaline media based on the Co-Mo-P/Zn-Co-S multicomponent heterostructure. The as-prepared multicomponent heterostructure was successfully obtained via a simple three-step hydrothermal-sulfidation-electrodeposition process consisting of star-like Co-Zn-S covered with Co-Mo-P. The structure and morphology evaluation of the...
Chromogenic detection of xylene isomers and luminogenic chemosensing of o-xylene employing a new macrocyclic cobalt complex: synthesis, and X-ray crystallographic, spectroscopic and computational studies
, Article New Journal of Chemistry ; Volume 46, Issue 43 , 2022 , Pages 20745-20754 ; 11440546 (ISSN) ; Asadi Mofarrah, L ; Jamjah, A ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
Here, we report the synthesis and characterization of a binuclear Co(ii) complex (Co2(2py)2Cl4) with two dinaphtho-diazacrown ether macrocyclic ligands, bearing two pyridine arms as a colourimetric and fluorescent sensor for detecting different xylene isomers as well as acting as a catalyst for the oxidation of o- and m-xylene under vacuum at room temperature. Chromogenic detection occurred when Co2(2py)2Cl4 was exposed to the xylene isomers, wherein the original blue colour of the complex changed to green and green-blue in the presence of o- and m-xylene, respectively. Meanwhile, no colour change was observed in the presence of the p-xylene isomer. Fluorescence spectroscopy revealed that...
Hierarchical nickel-cobalt sulfide/niobium pentoxide decorated green carbon spheres toward efficient energy storage
, Article Sustainable Energy and Fuels ; Volume 6, Issue 12 , 2022 , Pages 3042-3055 ; 23984902 (ISSN) ; Shahi, M ; Dubal, D. P ; Shahrokhian, S ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
Progression in the renewable energy field is tied to the development of high-performance energy storage devices with superior power and energy densities. Herein, an innovative material design was employed to prepare binder-free nickel-cobalt sulfide (NCS) on niobium pentoxide (Nb2O5)-decorated carbon spheres (CSs). Initially, CSs were directly grown on nickel foam (NF) via a hydrothermal carbonization approach. Core/shell-like NCS@Nb2O5@CS-NF was then synthesized through a hydrothermal process, followed by an electrodeposition process. When employed as an electrode material, NCS@Nb2O5@CS-NF achieved an excellent volumetric capacity of 9300 C L−1 at a current density of 18 A L−1. Later, an...
Cobalt vanadium chalcogenide microspheres decorated with dendrite-like fiber nanostructures for flexible wire-typed energy conversion and storage microdevices
, Article Nanoscale ; Volume 14, Issue 25 , 2022 , Pages 9150-9168 ; 20403364 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
The increasing energy demand for next-generation portable and miniaturized electronics has drawn tremendous attention to develop microscale energy storage and conversion devices with light weight and flexible characteristics. Herein, we report the preparation of flower-like cobalt vanadium selenide/nickel copper selenide (CoVSe/NiCuSe) microspheres with three-dimensional hierarchical structure of micropore growth on copper wire for a flexible fiber microsupercapacitor (microSC) and overall water splitting. The CoV-LDH microspheres are anchored on the dendrite-like NiCu nanostructured Cu wire using a hydrothermal method (CoV-LDH/NiCu@CW). The sulfidation and selenization of CoV-LDH/NiCu was...
Urchin-like hierarchical ruthenium cobalt oxide nanosheets on Ti3C2T: XMXene as a binder-free bifunctional electrode for overall water splitting and supercapacitors
, Article Nanoscale ; Volume 14, Issue 4 , 2022 , Pages 1347-1362 ; 20403364 (ISSN) ; Esfandiar, A ; Mehdipour, H ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
Synthesizing efficient electrode materials for water splitting and supercapacitors is essential for developing clean electrochemical energy conversion/storage devices. In the present work, we report the construction of a ruthenium cobalt oxide (RuCo2O4)/Ti3C2Tx MXene hybrid by electrophoretic deposition of Ti3C2Tx MXene on nickel foam (NF) followed by RuCo2O4 nanostructure growth through an electrodeposition process. Owing to the strong interactions between RuCo2O4 and Ti3C2Tx sheets, which are verified by density functional theory (DFT)-based simulations, RuCo2O4/Ti3C2Tx MXene@NF can serve as a bifunctional electrode for both water splitting and supercapacitor applications. This electrode...
Promising new catalytic properties of a Co (II)-carboxamide complex and its derived Co3O4 nanoparticles for the Mizoroki-Heck and the Epoxidation reactions
, Article Applied Organometallic Chemistry ; Volume 34, Issue 11 , November , 2020 ; Bagherzadeh, M ; Meghdadi, S ; Fadaei Tirani, F ; Babaie, M ; Schenk Joß, K ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
The new Co(II) - carboxamide complex (1) and Co3O4 nanoparticles (2), by way of thermal decomposition of (1) have been efficiently synthesised in the environment-friendly. X-ray diffraction reveals a slightly distorted octahedral coordination of cobalt (four nitrogens and two oxygens) in (1) and regular octahedral or tetrahedral ones (oxygens only) in (2). The investigation of (1) and (2) in the Mizoroki-Heck and epoxidation of alkens reactions showed them both to be powerful, green and inexpensive catalysts. © 2020 John Wiley & Sons, Ltd
Copper oxide@cobalt oxide core-shell nanostructure, as an efficient binder-free anode for lithium-ion batteries
, Article Journal of Physics D: Applied Physics ; Volume 54, Issue 46 , 2021 ; 00223727 (ISSN) ; Dehghan, P ; Zare, A. M ; Sanaee, Z ; Ghasemi, S ; Sharif University of Technology
IOP Publishing Ltd
2021
Abstract
Here, cobalt oxide nanostructures synthesized on vertically aligned copper oxide nanowires (NWs) have been investigated as a possible anode material for Lithium-ion batteries (LIBs). Copper oxide NWs were formed by thermal oxidation of electrochemically deposited copper on the stainless steel mesh substrate. The process used allows the formation of highly dense copper oxide NWs with excellent adhesion to the conductive current collector substrate. A simple hydrothermal method was implemented for the deposition of cobalt oxide nanostructures on the copper oxide NWs. The as-prepared binder-free copper oxide@cobalt oxide NWs electrode exhibits a high initial specific capacity of 460 mAh g-1 at...
Crystallinity of CoSi2 nanolayer grown by refractory metal interlayer and cap layer methods
, Article Journal of Physics: Conference Series ; Volume 100, Issue PART 4 , 2008 ; 17426588 (ISSN) ; Moshfegh, A. Z ; Sharif University of Technology
Institute of Physics Publishing
2008
Abstract
Epitaxial formation of CoSi2 nanolayer by solid state reaction of Co-Si in refractory metal intermediate-layer and cap-layer systems was investigated. Thin films of Ta and W, as the refractory metal intermediate or cap layers of the Co film, were deposited on Si(100) substrate and then heat-treated. The both interlayers resulted in formation of epitaxial CoSi 2 with (100) crystallographic orientation at 900°C. However, in the Ta intermediated system, the grown CoSi2 layer was thermally unstable at 1000°C, unlike the W system with a stable silicide layer. We found that use of W cap-layer cannot yield an epitaxial CoSi2 phase. But, a Ta cap-layer resulted in formation of epitaxial CoSi2(100)...
Novel multifunctional capacitor-varistor ceramics based on SnO2
, Article Ceramics International ; Volume 44, Issue 16 , 2018 , Pages 20386-20390 ; 02728842 (ISSN) ; Alipour, S ; Mahmoudi, P ; Karimi, A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Up to now, multifunctional varistor-capacitor materials were based on TiO2, even though these materials failed to have practical applications. For the first time, in this research, multifunctional varistor-capacitor properties are observed in the CuO-doped SnO2-CoO-Sb2O3 system. The XRD analysis showed that this system has a single phase microstructure. SEM images indicated that the CuO addition resulted in a better densification and larger grain size. The very low electric breakdown field of the CuO-doped SnO2-CoO-Sb2O3 system (12 V/mm, similar to TiO2), is a consequence of coarse-grained microstructure. This varistor had a suitable surge withstand capability as well. The colossal...