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Cobalt based Metal Organic Framework/Graphene nanocomposite as high performance battery-type electrode materials for asymmetric Supercapacitors
, Article Journal of Energy Storage ; 2020 ; Sedghi, A ; Hosseini, H ; Kashani, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Recently, development of advanced materials of metal-organic frameworks (MOFs) has attracted attention for the fabrication of supercapacitors (SCs) because of their high surface area and high level of porosity. However, poor electrical conductivity and weak mechanical properties of the MOFs have restricted their applications in the field. In this study, a one-step, in-situ synthesis of Cobalt-based MOF with graphene (CoMG nanocomposite) was employed to overcome the poor properties of MOFs. Accordingly, when the nanocomposite (CoMG5) was use as a supercapacitor electrode material, a specific capacitance (CS) of 549.96 F g−1 was observed in a three-electrode system with 6 M KOH electrolyte...
Electrocrystallization of Ni nanocones from chloride-based bath using crystal modifier by electrochemical methods
, Article Journal of Alloys and Compounds ; Volume 818 , 2020 ; Aliofkhazraei, M ; Dolati, A ; Rouhaghdam, A. S ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
The early stages of nucleation and growth of nanostructures can control the shape and final size of the fabricated nanostructure. Therefore, the study of the nucleation and growth mechanism of nanostructures is of great importance. The purpose of this study is to investigate the nucleation and growth mechanism of nickel nanocones from a chloride-based bath containing ethylene ammonium dichloride as a crystal modifier. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry tests were employed to investigate the nucleation and growth mechanism and also the mechanism of crystal modifier performance on the growth of nanocones. Electrochemical studies revealed...
In situ two-step preparation of 3D NiCo-BTC MOFs on a glassy carbon electrode and a graphitic screen printed electrode as nonenzymatic glucose-sensing platforms
, Article ACS Sustainable Chemistry and Engineering ; Volume 8, Issue 38 , 2020 , Pages 14340-14352 ; Shahrokhian, S ; Hosseini, H ; Sharif University of Technology
American Chemical Society
2020
Abstract
In the present study, a rational two-step strategy is employed for the green, fast, very simple, and highly controllable synthesis of the bimetallic nickel-cobalt-based metal-organic frameworks (MOFs) on glassy carbon substrates by in situ transformation of nickel-cobalt-layered double hydroxide nanosheet (NiCo-LDHs NSs) intermediates into nickel-cobalt-benzene tricarboxylic acid MOFs (E-NiCo-BTC MOFs). The structural characteristics of the electrode materials in each step were investigated via Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, elemental mapping, field emission scanning electron microscopy, and transmittance electron microscopy....
Study on spray-pyrolyzed In2S3 thin films, targeted as electron transport layer in solar energy
, Article Journal of Photonics for Energy ; Volume 10, Issue 2 , 2020 ; Heidariramsheh, M ; Ghorashi, S. M. B ; Taghavinia, N ; Mahdavi, S. M ; Sharif University of Technology
SPIE
2020
Abstract
Efficient electron transport layers (ETLs) play a pivotal role in the performance of solar cells. In recent years, Indium sulfide (In2S3) has been studied as a promising ETL in CuInGaS(e)2, Cu2ZnSnS(e)4, and perovskite solar cells. Despite several studies on spray-deposited In2S3, there is no complete experimental investigation on In2S3 thin films. The effect of the molar ratio of S/In and the type of indium precursor on the structural, morphological, optical, and electrical properties of sprayed-In2S3 layers has been studied. Films were characterized using x-ray diffraction, scanning electron microscopy (SEM), optical transmission (UV-Vis), Mott-Schottky analysis, four-point probe, and...
Development of a quartz crystal microbalance biodetector based on cellulose nanofibrils (CNFs) for glycine
, Article Journal of Materials Science: Materials in Electronics ; Volume 31, Issue 20 , 2020 , Pages 17451-17460 ; Iraji zad, A ; Vossoughi, M ; Kalantarian, A ; Sharif University of Technology
Springer
2020
Abstract
The performance of a quartz crystal microbalance (QCM) used as a sensor/detector relies on the performance and quality of the film coated onto the quartz crystal sensor. This study focuses on the sensor coating preparation for the detection of glycine. Cellulose nanofibrils (CNFs), natural polymers, were coated on a quartz crystal (QC) surface by a spin-coating method. The prepared CNF-coated QC was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), cyclic voltammetry (CV), Fourier transform infrared spectrophotometry-attenuated total reflectance (FTIR-ATR), Raman spectroscopy, and water contact angle (WCA). The stable and fully covered QCs without further...
Synthesis, characterisation and crystal structure of a new Cu(II)-carboxamide complex and CuO nanoparticles as new catalysts in the CuAAC reaction and investigation of their antibacterial activity
, Article Inorganica Chimica Acta ; Volume 506 , June , 2020 ; Bagherzadeh, M ; Meghdadi, S ; Fadaei Tirani, F ; Babaie, M ; Schenk Joß, K ; Sharif University of Technology
Elsevier S. A
2020
Abstract
The bidentate carboxamide ligand N-(thiazole-2-yl) picolinamide (LH) was synthesized in the environmentally friendly ionic liquid TBAB, and the five-coordinated CuII-complex, [Cu(L)2(H2O)].CHCl3 (1) was synthesized from LH and copper(II)acetate. Cupric oxide [CuO] nanoparticles (2) have been prepared by the thermal decomposition of (1) as a new precursor at 600 °C for 3 h under air atmosphere. (1) was characterised using FT-IR spectroscopy, elemental analyses and its solid state structure was confirmed by single crystal X-ray diffraction. (2) were identified by FT-IR spectroscopy, X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray analysis and thermo-gravimetric...
Catalytic and antibacterial properties of 3-dentate carboxamide Pd/Pt complexes obtained via a benign route
, Article Applied Organometallic Chemistry ; Volume 34, Issue 4 , April , 2020 ; Bagherzadeh, M ; Meghdadi, S ; Fadaei Tirani, F ; Schenk Joß, K ; Rabiee, N ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
The complexes PdII(qcq)(OAc) and PtII(qcq)Cl have been synthesized using environmentally benign synthesized ligands and characterized by elemental analyses: Fourier transform infrared spectroscopy, UV–visible spectroscopy, 1H NMR spectroscopy, and X-ray diffraction. The catalytic activity of the complex was assessed, in different media, for the Mizoroki–Heck coupling reaction for typical aryl halides and terminal olefins under aerobic conditions. Since the base and the solvent were found to influence the efficiency of the reaction, reaction conditions, temperature, time, and the amount of K3PO4 and a mixture of H2O/PEG, were optimized. We found, for the Mizoroki–Heck reaction coupling less...
ZnO nanoparticle/nanorod-based label-free electrochemical immunoassay for rapid detection of MMP-9 biomarker
, Article Biochemical Engineering Journal ; Volume 164 , 2020 ; Abdekhodaie, M. J ; Mousavi, S. A ; Taghipour, F ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A label-free electrochemical biosensor was developed for the rapid detection of the matrix metalloproteinase 9 (MMP-9) biomarker on the basis of antibody immobilizing on the zinc oxide (ZnO) nanoparticle and ZnO nanorod electrodes. The charge transfer resistance (Rct) of the electrodes was used as the indicator for MMP-9 concentration, which was obtained through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The ZnO nanorod-based biosensor exhibited linear behavior in the MMP-9 concentration range of 1–1000 ng/ml, which is a wider range than the available concentration ranges for most of the conventional methods. The biosensor sensitivity was 32.5 μA/(decade × cm2)...
Facile synthesis of N-doped hollow carbon nanospheres wrapped with transition metal oxides nanostructures as non-precious catalysts for the electro-oxidation of hydrazine
, Article Journal of Electroanalytical Chemistry ; Volume 873 , 2020 ; Rezaee, S ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V
2020
Abstract
In the present work, N-doped hollow carbon nanospheres (N-HCNSs) is prepared by direct carbonization of polyaniline-co-polypyrrole (PACP) hollow spheres without template needing. Two different NiO nanostructures (nanosheets and nanowires) are prepared by forming a shell around the N-HCNSs via simple hydrothermal/calcination processes (NiO-NSs@N-HCNSs and NiO-NWs@N-HCNSs). The morphology and structure of the nanostructures are characterized using field emission scanning electron microscopy (FE-SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The prepared nanocomposites are used as catalysts for the electrocatalytic...
Investigation of the interfacial electron transfer kinetics in ferrocene-terminated oligophenyleneimine self-assembled monolayers
, Article Langmuir ; Volume 36, Issue 42 , 2020 , Pages 12572-12579 ; Sharif University of Technology
American Chemical Society
2020
Abstract
In this article, the synthesis, characterization, and cyclic voltammetry (CV) measurements are reported for ferrocene-terminated oligophenyleneimine (OPI_Fc) and ferrocene-terminated conjugation-broken oligophenyleneimine (CB-OPI_Fc) self-assembled monolayers (SAMs) in two different electrolytes, namely, 1-ethyl-3-methylimidazolium-bis (trifluoromethyl-sulfonyl) imide (EMITFSI) ionic liquid and tetrabutylammonium hexafluorophosphate (Bu4NPF6) in acetonitrile (0.1 M solution). The SAMs were synthesized on Au surfaces by the sequential imine condensation reactions. CV was used to investigate the kinetics of electron transfer (ET) to the ferrocene, and it was observed that the standard ET rate...
An electrochemical sensing platform based on nitrogen-doped hollow carbon spheres for sensitive and selective isoprenaline detection
, Article Journal of Electroanalytical Chemistry ; Volume 847 , 2019 ; 15726657 (ISSN) ; Panahi, S ; Salimian, R ; Sharif University of Technology
Elsevier B.V
2019
Abstract
In this work, uniform and monodisperse hollow carbon spheres (HCSs) are synthesized through two different processes using polydopamine (PDA), as a carbon precursor, and silica core as a template, under the modified Stöber condition. The surface morphology of the synthesized structures is characterized by means of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and Fourier-transform infrared spectroscopy (FT-IR). In the next step, the electrochemical behavior of isoprenaline (ISPN) is investigated by using glassy carbon electrode modified with a thin film of the synthesized hollow carbon spheres. The electrochemical characterization of the modified electrodes is...
Development of a sensitive diagnostic device based on zeolitic imidazolate frameworks-8 using ferrocene-graphene oxide as electroactive indicator for pseudomonas aeruginosa detection
, Article ACS Sustainable Chemistry and Engineering ; Volume 7, Issue 15 , 2019 , Pages 12760-12769 ; 21680485 (ISSN) ; Ranjbar, S ; Sharif University of Technology
American Chemical Society
2019
Abstract
Since Gram-negative bacteria have a predominant role in nosocomial infections, there are high demands to develop a fast and sensitive method for diagnosis of bacteria in clinical samples. To address this challenge, we designed a novel electrochemical biosensor based on aptamers immobilized in engineered zeolitic imidazolate Framework-8 (ZIFs-8) via EDC-NHS chemistry. Cyclic voltammetry and electrochemical impedance spectroscopy techniques were conducted to monitor the electrochemical characterization. With respect to unique π-πinteractions between aptamer and graphene oxide (GO), the differential pulse voltammetry technique was applied with ferrocene-graphene oxide (Fc-GO) as an...
Shedding light on pseudocapacitive active edges of single-layer graphene nanoribbons as high-capacitance supercapacitors
, Article ACS Applied Energy Materials ; Volume 2, Issue 5 , 2019 , Pages 3665-3675 ; 25740962 (ISSN) ; Esfandiar, A ; Mehdipour, H ; Chaigneau, M ; Irajizad, A ; Moshfegh, A. Z ; Sharif University of Technology
American Chemical Society
2019
Abstract
In the field of energy storage by high-rate supercapacitors, there has been an upper limit for the total interfacial capacitance of carbon-based materials. This upper limit originates from both quantum and electric double-layer capacitances. Surpassing this limit has been the focus of intense research in this field. Here, we precisely investigate the effect of chemical functional groups and physical confinement on the electrochemical performance of graphene nanoribbons. We present the results of a quasi-one-dimensional single-layer graphene nanoribbon (120 nm in width and -100 μm in length) microelectrode fabricated by mechanical exfoliation of graphite, followed by electron beam lithography...
Enhanced electrochemical activity of a hollow carbon sphere/polyaniline-based electrochemical biosensor for HBV DNA marker detection
, Article ACS Biomaterials Science and Engineering ; Volume 5, Issue 5 , 2019 , Pages 2587-2594 ; 23739878 (ISSN) ; Shahrokhian, S ; Panahi, S ; Sharif University of Technology
American Chemical Society
2019
Abstract
Herein, we present a novel, simple, and ultrasensitive electrochemical DNA (E-DNA) sensor based on hollow carbon spheres (HCS) decorated with polyaniline (PANI). A thiolated 21-mer oligonucleotide, characteristic of HBV DNA, is immobilized via electrodeposited gold nanoparticles on HCS-PANI. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) are used to characterize the electrochemical properties of the prepared nanocomposite. Scanning electron microscopy is employed to investigate the morphological texture of the fabricated modifier. An enhanced intrinsic signal of PANI is probed to evaluate the biosensing ability of the prepared...
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....
Electrochemical sensors based on functionalized carbon nanotubes modified with platinum nanoparticles for the detection of sulfide ions in aqueous media
, Article Journal of Chemical Sciences ; Volume 131, Issue 3 , 2019 ; 09743626 (ISSN) ; Dolati, A ; Salmani Rezaie , S ; Sharif University of Technology
Springer
2019
Abstract
Abstract : Vertically aligned carbon nanotube (CNT) arrays were synthesized by thermal chemical vapor deposition (CVD) on stainless steel substrates coated by cobalt nanoparticles as catalyst. Morphological and elemental analyses conducted by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that bamboo-like CNTs were blocked by Co nanoparticles at the tips. The fabricated nanotubes underwent functionalization by electrochemical oxidation in sulfuric acid, and the subsequent structural studies, as well as Fourier transform infrared (FTIR) spectroscopy confirmed that the tips of functionalized CNTs were opened while oxygenated functional groups were...
Design and fabrication of an electrochemical aptasensor using Au nanoparticles/carbon nanoparticles/cellulose nanofibers nanocomposite for rapid and sensitive detection of Staphylococcus aureus
, Article Bioelectrochemistry ; Volume 123 , 2018 , Pages 70-76 ; 15675394 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Since that pathogenic bacteria are major threats to human health, this paper describes the fabrication of an effective and durable sensing platform based on gold nanoparticles/carbon nanoparticles/cellulose nanofibers nanocomposite (AuNPs/CNPs/CNFs) at the surface of glassy carbon electrode for sensitive and selective detection of Staphylococcus aureus (S. aureus). The AuNPs/CNPs/CNFs nanocomposite with the high surface area, excellent conductivity, and good biocompatibility was used for self-assembled of the thiolated specific S. aureus aptamer as a sensing element. The surface morphology of AuNPs/CNPs/CNFs nanocomposite was characterized with field emission scanning electron microscopy...
Vertically standing Cu2O nanosheets promoted flower-like PtPd nanostructures supported on reduced graphene oxide for methanol electro-oxidation
, Article Electrochimica Acta ; Volume 259 , 2018 , Pages 36-47 ; 00134686 (ISSN) ; Rezaee, S ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The present study reports a simple electrochemical approach to the fabrication of a new nanocomposite containing PtPd nanoflowers (NFs) promoted with two-dimensional (2D) nanosheets (NSs) structure cuprous oxide (Cu2O) supported on reduced graphene oxide (rGO) (PtPd-NFs/Cu2O-NSs/rGO). Scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectra, Raman spectroscopy, and energy dispersive X-ray spectroscopy are used for characterization of the PtPd-NPs/Cu2O-NPs/rGO. SEM images showed that vertical-standing arrays of Cu2O with an edge length up to 1 μm and thickness of about 20 nm are electrodeposited on the surface of rGO film. Also, PtPd needle-like NFs with visible and...
Ultrasensitive detection of cancer biomarkers using conducting polymer/electrochemically reduced graphene oxide-based biosensor: Application toward BRCA1 sensing
, Article Sensors and Actuators, B: Chemical ; Volume 266 , 2018 , Pages 160-169 ; 09254005 (ISSN) ; Salimian, R ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Breast Cancer (BRCA) is the most common threat in women worldwide. Increasing death rate of diagnosed cases is the main leading cause of designing specific genosensors for BRCA − related cancer detection. In the present study, an ultrasensitive label − free electrochemical DNA (E − DNA) sensor based on conducting polymer/reduced graphene − oxide platform has been developed for the detection of BRCA1 gene. An electrochemical method was applied as a simple and controllable technique for the electrochemical reduction of graphene oxide and also, electro − polymerization of pyrrole − 3 − carboxylic acid monomer. The results of the present work show that the polymer − coated reduced graphene −...
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...