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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...
Predicting the cardiac troponin I (cTnI) aptamer/methylene blue configuration using computational modeling studies: a screening search method for constructing aptasensors
, Article ChemistrySelect ; Volume 5, Issue 35 , September , 2020 , Pages 10958-10969 ; Khajehsharifi, H ; Hashemnia, S ; Shahrokhian, S ; Sharif University of Technology
Wiley-Blackwell
2020
Abstract
Acute Myocardial Infarction (AMI) is the most common cause of mortality, and cardiac troponin I (cTnI) is the gold standard for AMI diagnosis. Some aptamers have been reported to detect cTnI, but there is rarely any structural information on their binding with cTnI. There are many studies involving electrochemical aptasensors with methylene blue (MB) as a redox indicator that does not provide any significant new information. Our study, however, involves the computational modeling of the complexes of a documented 40-mer ssDNA-cTnI aptamer with its target and MB. Here, MB was used as a model system to investigate the rather complex interaction modes between small redox molecules and a...
Transition metal ions-doped polyaniline/graphene oxide nanostructure as high performance electrode for supercapacitor applications
, Article Journal of Solid State Electrochemistry ; Volume 22, Issue 4 , 2018 , Pages 983-996 ; 14328488 (ISSN) ; Shahrokhian, S ; Iraji Zad, A ; Sharif University of Technology
Springer New York LLC
2018
Abstract
Polyaniline/graphene oxide (PANI/GO) co-doped with Zn2+ and Fe3+ was synthesized via a simple and low cost one-step chronoamperometry method on stainless steel (SS) as the substrate. The Fe3+-Zn2+-PANI/GO nanocomposite is characterized using X-ray diffraction as well as Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and field emission scanning electron microscopy. Also, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy are used to study the electrochemical performance of the as-prepared electrode materials. Significantly, the Fe3+-Zn2+-PANI/GO nanocomposite exhibits a specific...
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...
Fabrication of a 2.8 V high-performance aqueous flexible fiber-shaped asymmetric micro-supercapacitor based on MnO2/PEDOT:PSS-reduced graphene oxide nanocomposite grown on carbon fiber electrode
, Article Journal of Materials Chemistry A ; Volume 8, Issue 37 , 2020 , Pages 19588-19602 ; Shahrokhian, S ; Soavi, F ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Flexible and lightweight fiber-shaped micro-supercapacitors have attracted tremendous attention as next-generation portable electronic devices, due to their high flexibility, tiny volume, and wearability. Herein, we successfully fabricated a ternary binder-free nanocomposite of MnO2/PEDOT:PSS-rGO on a carbon fiber substrate for application in high performance fiber-shaped micro-supercapacitors. The synergistic effects of the different components in the fiber-shaped electrode help to deliver a high specific capacitance of 2.9 F cm-2 (194 F cm-3 and 550 mF cm-1) at a current density of 5 mA cm-2 and a long cycle life with 95% capacitance retention after 5000 cycles in 1 M Na2SO4 electrolyte. A...
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...
Direct fabrication of phosphorus-doped nickel sulfide and eco-friendly biomass-derived humic acid as efficient electrodes for energy storage applications
, Article Sustainable Energy and Fuels ; Volume 5, Issue 19 , 2021 , Pages 4869-4881 ; 23984902 (ISSN) ; Shahi, M ; Shahrokhian, S ; Sharif University of Technology
Royal Society of Chemistry
2021
Abstract
Development of renewable energies is in parallel with improving high-performance energy storage devices, which can store maximum solar or wind energy and power. Herein, asymmetric energy storage systems are constructed from phosphorus-doped nickel sulfide (P-doped NiS) and biomass-derived humic acid (HA) as positive and negative electrodes, respectively. Initially, nickel sulfide (NiS) nanostructures are directly grown onto nickel foam (NF) via a hydrothermal step. P-doping into the NiS bulk is carried out through a simple hydrothermal process as well. Also, HA is activated via carbonization treatment (A-HA) for employing as the negative electrode's active material. The P-doped NiS-NF...
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...
Hierarchical core-shell structure of ZnO nanotube/MnO2 nanosheet arrays on a 3D graphene network as a high performance biosensing platform
, Article RSC Advances ; Volume 6, Issue 66 , 2016 , Pages 61190-61199 ; 20462069 (ISSN) ; Shahrokhian, S ; Iraji zad, A ; Sharif University of Technology
Royal Society of Chemistry
Abstract
A hierarchical core-shell structure composed of ZnO nanotubes/MnO2 nanosheets was fabricated via a two-step electrochemical deposition procedure on the surface of a 3D graphene network (3DGN) as a free-standing monolithic electrode. In the first step, ZnO nanorod arrays were grown on the surface of a 3DGN followed by electrochemical deposition of MnO2 nanosheets in the next step, which caused the inner parts of initial ZnO nanorods to etch away and resulted in the formation of ZnO nanotubes (ZnO NTs). The highly porous interconnected graphene backbone offers very high conductivity and a large accessible surface area. On the other hand, the formation of ZnO nanotubes can enhance the...
Numerical simulation of a microfluidic system for regular glucose measurement
, Article 26th National and 4th International Iranian Conference on Biomedical Engineering, ICBME 2019, 27 November 2019 through 28 November 2019 ; 2019 , Pages 60-65 ; 9781728156637 (ISBN) ; Saidi, M. S ; Shahrokhian, S ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
The aim of this research is to design an implantable integrated microfluidic system in order to regularly measure the glucose level in the human body, nonenzymatically, using the microdialysis method. The main compartments of this system are a micropump, array of hollow microneedles and an electrochemical sensor. At the base of the microneedles, there are located semipermeable membranes, that when the pumped dialysis fluid passes over them, the glucose of the interstitial fluid diffuses into the dialysis fluid and then, in the sensor section, it is measured nonenzymatically using the amperometry method. Both the arrangement of the miconeedles and the amount of the dialysis fluid flow are...
Synthesis, characterization, and comparison of two new copper(II)complexes containing Schiff-base and diazo ligands as new catalysts in CuAAC reaction
, Article Inorganica Chimica Acta ; Volume 492 , 2019 , Pages 213-220 ; 00201693 (ISSN) ; Mahmoudi, H ; Ataie, S ; Hafezi-Kahnamouei, M ; Shahrokhian, S ; Bellachioma, G ; Vaccaro, L ; Sharif University of Technology
Elsevier S.A
2019
Abstract
Two copper(II)complexes were synthesized through the reaction of Cu(OAc)2·H2O with a Schiff-base ligand (1-(((3,4-dichlorophenyl)imino)methyl)naphthalen-2-ol)and a diazo ligand (1-((3,4-dichlorophenyl)diazenyl)naphthalen-2-ol)in methanol. The complexes and ligands were characterized employing elemental analysis and electronic spectra. In addition, the ligands were fully characterized by using several 1D and 2D NMR techniques. Single crystal X-ray crystallography was also used for the characterization of some of these materials. Due to finding out the effect of Schiff-base and diazo ligands nature on the catalytic activity, the complexes were catalytically compared in one-pot azide-alkyne...
Silver fiber fabric as the current collector for preparation of graphene- based supercapacitors
, Article Electrochimica Acta ; Volume 227 , 2017 , Pages 246-254 ; 00134686 (ISSN) ; Shahrokhian, S ; Iraji zad, A ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
During the past few years, a considerable attention has been devoted to the development of textile- based energy storage devices and wearable electronics applications. In this paper, for the first time, we report a flexible high performance graphene-based supercapacitor using silver fiber fabric as the current collector. The silver fiber fabric offers remarkable advantages such as light weight, mechanical flexibility and ease of integration with electronic textiles, which well-suited for wearable energy storage devices. A new hybrid material of graphene-silver fiber fabric (rGO/SFF) was prepared through a facile electrophoretic deposition of graphene and being used as a binder-free flexible...
An efficient two-step approach for improvement of graphene aerogel characteristics in preparation of supercapacitor electrodes
, Article Journal of Energy Storage ; Volume 17 , 2018 , Pages 465-473 ; 2352152X (ISSN) ; Shahrokhian, S ; zad, A. I ; Asadian, E ; Hosseini, H ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
We fabricated a high rate capability supercapacitor based on fluorine-doped graphene-carbon nanotubes aerogel network (G-CNT-F). Based on the electrochemical impedance spectroscopy data, the fluorination decreases the charge transfer resistance of graphene sheets, while CNTs act as spacer in the 3D structure. Therefore, both treatments improved the electrochemical properties of the resulted aerogel. Based on the Fourier transform infrared spectroscopy and XPS results, these excellent performances are attributed to semi-ionic bonds between fluorine and carbon. The specific capacitance of the graphene aerogel showed 78% decrease, when discharge current increases from 2 to 40 mA, while the...
Vanadium dioxide-anchored porous carbon nanofibers as a Na+ intercalation pseudocapacitance material for development of flexible and super light electrochemical energy storage systems
, Article Applied Materials Today ; Volume 10 , 2018 , Pages 72-85 ; 23529407 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The development of a flexible binder free electrode based on 3D vanadium dioxide (VO2) nano-architectures has materialized as an effective strategy for fabrication of advanced wearable, portable, and stretchable electronic devices. However, most of the stretchable energy storage devices based on VO2 suffer from a relatively low operating voltage, high weight, low specific capacitance, and thus low energy density. Here, a novel binder free supercapacitor electrode composed of hierarchical VO2 nanosheet arrays grown on porous carbon nanofibers (VO2@PCNFs) is designed using a simple hydrothermal method followed by annealing treatment. The electrochemical evaluation confirmed that the energy...
Hydrogen bubble template fabricated nano-architecture quaternary dendritic sulfide as cathode and electro-etched carbon fiber paper as anode electrode for total novel binder-free asymmetric supercapacitors
, Article Journal of Alloys and Compounds ; Volume 811 , 2019 ; 09258388 (ISSN) ; Naderi, L ; Shahrokhian, S ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
A novel electrode consisting of 3D porous nickel‒cobalt‒copper sulfide dendritic structures is synthesized, in which, for the first time ternary Ni–Co–Cu foam is constructed through hydrogen bubble template and followed by sulfidization via a hydrothermal reaction in thiourea. The 3D, porous Ni–Co–Cu dendritic sulfide electrode exhibits a high specific capacitance of 1203.75 F g−1 (0.963 F cm−2) at current of 1.0 mA and excellent cycling stability, excellent ratability along with high cycle stability. An asymmetric supercapacitor (ASC) using dendritic sulfide structures and reduced electro-etched carbon fiber paper (RECF) as the positive and negative electrodes, respectively is developed....
Direct growth of nickel-cobalt oxide nanosheet arrays on carbon nanotubes integrated with binder-free hydrothermal carbons for fabrication of high performance asymmetric supercapacitors
, Article Composites Part B: Engineering ; Volume 172 , 2019 , Pages 41-53 ; 13598368 (ISSN) ; Shahrokhian, S ; Hosseini, H ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
A high performance asymmetric supercapacitor (ASC)has been fabricated by using nickel oxide-cobalt oxide nanosheets (NiO–CoO NSs), which were directly grown on carbon nanotubes (CNTs)and hydrothermal carbon spheres (HTCs)as positive and negative electrodes, respectively. Both electrode materials are binder-free prepared by using a catalytic chemical vapour deposition (CVD)approach followed by a facile hydrothermal method for cathode and a one-step environmental-friendly route called hydrothermal carbonization for anode. Using NiO–CoO NSs@CNTs and HTCs, which were directly grown on Ni foam, not only leads to a very small equivalent series resistance, but also provides an impressive capacitive...
One step synthesis of SnS2-SnO2 nano-heterostructured as an electrode material for supercapacitor applications
, Article Journal of Alloys and Compounds ; Volume 782 , 2019 , Pages 38-50 ; 09258388 (ISSN) ; Haghighi, M ; Shahrokhian, S ; Taghavinia, N ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
SnS2-SnO2 nano-heterostructures are synthesized with two different precursors of thioacetamide (TAA) and thiourea (TU) at various solvent ratios (SR) of ethanol and water by using a facile, economical, scalable, and cost-effective solvothermal method. The obtained products have been characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), and Brunauer–Emmet–Teller (BET) techniques. It is found that different precursors and various SR values have an influence on the composition and morphologies of the prepared nanostructures, leading to variation in capacitive behavior of the fabricated electrodes....