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Electrochemical Behaviors of RuO2-TiO2 Mixed Metal Oxide Coated on Titanium Anodes in Chlor-Alkali Electrolysis
, M.Sc. Thesis Sharif University of Technology ; Ghorbani, Mohammad (Supervisor)
Abstract
Titanium anodes activated by noble metal oxides under the trade name of dimensionally stable anodes (DSAs) are widely used in the electrolytic industry, particularly in chlor – alkali electrolysis. Over 20 years of use, the fundamental aspects of their long – lasting performance are not fully understand and the corrosion mechanisms are still the subject of many investigations. RuO2 – TiO2 coatings on titanium substrate, due to proper electrochemical characteristics and good corrosion resistance, is most applicable as an anode in chlor – alkali systems. In the present investigation, the first layer of Pt – Ir coating is applied via electrodeposition method on the pretreated titanium substrate...
Specific picomolar detection of a breast cancer biomarker her-2/neu protein in serum: electrocatalytically amplified electroanalysis by the aptamer/peg-modified electrode
, Article ChemElectroChem ; Volume 4, Issue 4 , 2017 , Pages 872-879 ; 21960216 (ISSN) ; Kékedy Nagy, L ; Ferapontova, E. E ; Sharif University of Technology
Wiley-VCH Verlag
2017
Abstract
Specific and sensitive electroanalysis of blood-circulating protein cancer biomarkers is often complicated by interference from serum proteins nonspecifically adsorbing at the biosensing interface and masking specific reactions of interest. Here, we have developed an electrocatalytically amplified assay for specific and sensitive analysis of human epidermal growth factor receptor-2 (HER-2/neu, a protein cancer biomarker over-expressed in breast cancers) that allows us to avoid both the interference from bovine serum albumin (BSA) and electrocatalytic amplification of the signal stemming from the specific aptamer−HER-2/neu binding. A HER-2/neu-specific thiolated aptamer sequence was...
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...
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...
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...
Direct growth of metal-organic frameworks thin film arrays on glassy carbon electrode based on rapid conversion step mediated by copper clusters and hydroxide nanotubes for fabrication of a high performance non-enzymatic glucose sensing platform
, Article Biosensors and Bioelectronics ; Volume 112 , 2018 , Pages 100-107 ; 09565663 (ISSN) ; Khaki Sanati, E ; Hosseini, H ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The direct growth of self-supported metal-organic frameworks (MOFs) thin film can be considered as an effective strategy for fabrication of the advanced modified electrodes in sensors and biosensor applications. However, most of the fabricated MOFs-based sensors suffer from some drawbacks such as time consuming for synthesis of MOF and electrode making, need of a binder or an additive layer, need of expensive equipment and use of hazardous solvents. Here, a novel free-standing MOFs-based modified electrode was fabricated by the rapid direct growth of MOFs on the surface of the glassy carbon electrode (GCE). In this method, direct growth of MOFs was occurred by the formation of vertically...
Efficient electrocatalytic oxidation of water and glucose on dendritic-shaped multicomponent transition metals/spongy graphene composites
, Article Electrochimica Acta ; Volume 386 , 2021 ; 00134686 (ISSN) ; Mohammadi, R ; Mojaddami, M ; Rahmati, R ; Hemmati, A ; Simchi, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
To improve the efficiency of electrochemical processes for environmental remediation, we present a new type of hybrid nanomaterials based on leaf-like copper-based quaternary transition metals and spongy monolayer graphene. To demonstrate the functionality of the hybrid electrocatalyst, fast and competent electrooxidation of water and glucose is shown. The mechanism of improved catalysis is ascribed to the synergetic catalytic effect of quaternary Cu-Ni-Fe-Co alloy with dendritic morphology along with the highly conductive and spongy structure of the graphene monolayer. It is shown that water oxidation can be performed at a low overpotential of 315 mV to reach a current denisty of 100 mA...
Nickel-based nanosheets array as a binder free and highly efficient catalyst for electrochemical hydrogen evolution reaction
, Article International Journal of Hydrogen Energy ; Volume 47, Issue 82 , 2022 , Pages 34887-34897 ; 03603199 (ISSN) ; Hemmati, K ; Mirabbaszadeh, K ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Hydrogen technology through water electrolyzer systems has attracted a great attention to overcome the energy crisis. So, rationally designed non-noble metal based-electrocatalysts with high activity and durability can lead to high performance water electrolyzer systems and high purity hydrogen generation. Herein, a facile two-step method: hydrothermal and electrodeposition, respectively, are developed to decorate highly porous three-dimensional binder-free structure NiFeO/NiO nanosheets array on Ni foam (NiFeO/NiO/NF) with robust adhesion as a high-performance electrode for Hydrogen Evolution Reaction (HER). The electrodeposition process applied after the initial hydrothermal process...
Enhanced electrochemical activity of Co3O4/Co9S8 heterostructure catalyst for water splitting
, Article International Journal of Hydrogen Energy ; Volume 47, Issue 72 , Volume 47, Issue 72 , 2022 , Pages 30970-30980 ; 03603199 (ISSN) ; Ahmad, I ; Rashid, N ; Zafar, M. N ; Shehzad, F. K ; ullah, Z ; Ul-Hamid, A ; Nazar, M. F ; Junaid, M ; Faheem, M ; Shafqat, S. S ; Jabeen, U ; Dahshan, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The dearth of efficient, robust, and economical electrocatalysts for water oxidation is dubiously the key obstacle for renewable energy devices, so synthesis of efficient, and cost-effective metal-based water oxidation catalysts is vital. Herein, Co3O4, Co9S8 catalysts and their heterostructure Co3O4/Co9S8 were synthesized and evaluated as water oxidation electrocatalysts. The characterization of Co3O4, Co9S8, and Co3O4/Co9S8 electrocatalysts was performed using Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction techniques. The heterostructure Co3O4/Co9S8 (1.46 V) exhibited water oxidation electrocatalysis at extremely low onset potential compared to...
New high-entropy transition-metal sulfide nanoparticles for electrochemical oxygen evolution reaction
, Article Electrochimica Acta ; 2022 , Volume 436 ; 00134686 (ISSN) ; Hasanvandian, F ; Bahadoran, A ; Shokri, A ; Zerangnasrabad, S ; Kakavandi, B ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Developing extremely efficient electrocatalysts for oxygen evolution reactions (OER) is a decisive step toward the progression of rechargeable metal-oxygen batteries, CO2 reduction, and water-splitting. Nanoporous high-entropy transition-metal sulfides (np-HETMS) represent a new generation of promising OER catalysts by virtue of their exceptional catalytic activity. However, their synthesis maintains to be a challenge by reason of the thermodynamic immiscibility of the constituting multi-principal metallic elements in the sulfide structure. Herein, for the first time, the np-HETMS ((CoFeNiMnCu)S2) nanoparticles with pyrite-phase was synthesized via a facile and easy adaptable...
Electrocatalytic oxidation of methane at nickel hydroxide modified nickel electrode in alkaline solution
, Article Electrochemistry Communications ; Volume 5, Issue 2 , 2003 , Pages 184-188 ; 13882481 (ISSN) ; Mahjani, M. G ; Heli, H ; Gobal, F ; Heydarpoor, M ; Sharif University of Technology
Elsevier Inc
2003
Abstract
Nickel hydroxide modified nickel electrodes prepared by cycling the potential of a nickel electrode in alkaline solution exhibited electrocatalytic activity for the oxidation of methane in alkaline media. In the presence of methane the oxidation peak current of nickel hydroxide increases while that of the reverse process decreases. This is attributed to the mediation of nickel species, probably β-NiOOH phase, in the process of electrocatalysis. The mechanism of methane oxidation has also been discussed in terms of the formations of intermediates normally encountered in small organics electro-oxidation. It has also been suggested that in the further oxidation of the intermediates, ions in the...
A low cost and highly active non-noble alloy electrocatalyst for hydrazine oxidation based on nickel ternary alloy at the surface of graphite electrode
, Article Journal of Electroanalytical Chemistry ; Volume 763 , 2016 , Pages 134-140 ; 15726657 (ISSN) ; Rostami, T ; Mahjani, M. G ; Gobal, F ; Sharif University of Technology
Elsevier B.V
2016
Abstract
The electrocatalytic oxidation of hydrazine was studied over Ni, Cu, Co and Ni-based ternary alloy on graphite electrodes in alkaline solution. The catalysts were prepared by cycling the graphite electrode in solutions containing Ni, Cu and Co ions at cathodic potentials. The synergistic effects and the catalytic activity of the modified electrodes were investigated by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). It was found that, in the presence of hydrazine, the modified Ni-based ternary alloy electrode (G/NiCuCo) exhibited a good catalytic activity for the oxidation of hydrazine at a reduced overpotential and it has a significant high...
Facile synthesis of petal-like NiCo/NiO-CoO/nanoporous carbon composite based on mixed-metallic MOFs and their application for electrocatalytic oxidation of methanol
, Article Applied Catalysis B: Environmental ; Volume 244 , 2019 , Pages 802-813 ; 09263373 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Porous carbon template decorated with mixed transition metals/metal oxides with tunable architecture is becoming increasingly important and attractive as a kind of novel electrode materials. In this way, mixed-metallic metal-organic frameworks (MOFs) provide an opportunity for fabrication of homogeneous mixed metals/metal oxides distribution in the porous carbon frame without any carbon precursor additive. Also, structures, dimensions and electrochemical performance of MOFs can be readily manipulated by simply tuning the metals molar ratio. In this study, we demonstrate the design and fabrication of petal-like NiCo/NiO-CoO metal/metal oxides with a rational composition embedded in 3D...
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...
Electrocatalytic oxidation and nanomolar determination of guanine at the surface of a molybdenum (VI) complex-TiO2 nanoparticle modified carbon paste electrode
, Article Journal of Electroanalytical Chemistry ; Volume 624, Issue 1-2 , 2008 , Pages 73-78 ; 15726657 (ISSN) ; Taleat, Z ; Beitollahi, H ; Salavati Niasari, M ; Mirjalili, B. B. F ; Taghavinia, N ; Sharif University of Technology
Elsevier
2008
Abstract
A modified carbon paste electrode was prepared by incorporating TiO2 nanoparticles with bis[bis(salicylidene-1,4-phenylenediamine)molybdenum(VI)]. A mixture of fine graphite powder with 4 wt% of TiO2 nanoparticles was applied for the preparation of the carbon paste (by dispersing in paraffin) and finally modified with a molybdenum (VI) complex. The electrocatalytic oxidation of guanine (G) was investigated on the surface of the molybdenum (VI) complex-TiO2 nanoparticle modified carbon paste electrode (MCTNMCPE) using cyclic voltammetry (CV), differential pulse voltammetry (DPV), chronoamperometry (CHA) and chronocoloumetry (CHC). Using the modified electrode, the kinetics of G...
Electrocatalytic oxidation of penicillamine at a carbon paste electrode modified with cobalt salophen
, Article Journal of Electroanalytical Chemistry ; Volume 565, Issue 1 , 2004 , Pages 95-101 ; 15726657 (ISSN) ; Souri, A ; Khajehsharifi, H ; Sharif University of Technology
Elsevier
2004
Abstract
Electrocatalytic oxidation of penicillamine (PA) at a carbon paste electrode chemically modified with cobalt salophen as a schiff base complex (CoSal) was thoroughly investigated. The results of cyclic voltammetry (CV) and polarization studies were used for the prediction of the mechanism of electrochemical oxidation of PA mediated with CoSal at the surface of a modified electrode. The performance of the modified electrode was compared with those of electrodes modified with cobalt phthalocyanine (CoPc). In comparison, CoSal appears to be considerably more effective as a catalyst for reduction of the overpotential of the anodic oxidation of PA, resulting in a very sharp anodic CV peak at...
Mesoporous nanostructured composite derived from thermal treatment CoFe prussian blue analogue cages and electrodeposited NiCo-S as an efficient electrocatalyst for an oxygen evolution reaction
, Article ACS Applied Materials and Interfaces ; Volume 12, Issue 14 , 2020 , Pages 16250-16263 ; Shahrokhian, S ; Sharif University of Technology
American Chemical Society
2020
Abstract
Developing effective and priceless electrocatalysts is an indispensable requirement for advancing the efficiency of water splitting to get clean and sustainable fuels. Herein, we reported a feasible strategy for preparing a trimetallic (NiCoFe) superior electrocatalyst with a novel open-cage/3D frame-like structure for an oxygen evolution reaction (OER). It is prepared by consequent thermal treatments of a CoFe Prussian blue analogue frame/cage-like structure under an argon (CoFeA-TT) atmosphere and then electrochemical deposition of nickel-cobalt sulfide nanosheets as a shell layer on it. The electrochemical measurements demonstrated that the deposition of NiCo-S on CoFeA-TT...
Kinetic interpretation of a negative time constant impedance of glucose electrooxidation
, Article Journal of Physical Chemistry B ; Volume 112, Issue 49 , 2008 , Pages 15933-15940 ; 15206106 (ISSN) ; Jafarian, M ; Forouzandeh, F ; Gobal, F ; Mahjani, M. G ; Sharif University of Technology
American Chemical Society
2008
Abstract
Nickel - copper alloy modified glassy carbon electrodes (GC/NiCu) prepared by galvanostatic deposition were used for the electrocatalytic oxidation of glucose in alkaline solutions. The electro-oxidation of glucose in a 1 M NaOH solution at different concentration of glucose was studied by the method of ac-impedance spectroscopy. The impedance behavior show different patterns, capacitive, and inductive loops and negative resistances, at different applied anodic potential. The influence of the electrode potential on the impedance pattern is studied and a quantitative explanation for the impedance behavior of glucose oxidation is put forward by a proposed mathematical model. At potentials...
Ultrafast two-step synthesis of s-doped Fe/Ni (Oxy)Hydroxide/Ni nanocone arrays on carbon cloth and stainless-steel substrates for water-splitting applications
, Article ACS Applied Energy Materials ; Volume 4, Issue 10 , 2021 , Pages 10627-10638 ; 25740962 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
American Chemical Society
2021
Abstract
Nonprecious and effective electrocatalyst development is an essential requirement for boosting water-splitting efficiency to obtain clean and sustainable fuels for future renewable energy demands. Herein, we reported an ultrafast and feasible strategy for constructing an S-doped bimetallic iron/nickel oxy(hydroxide) (S-(Fe/Ni)OOH) as a superior electrocatalyst for oxygen evolution reaction (OER). It is prepared by consequent electroplating of nickel nanocone arrays (NiNCAs) on carbon cloth (CC) and stainless-steel mesh (SSM) and then formation of S-(Fe/Ni)OOH layers on them by ultrafast one-step oxidation solution-phase method in the solution of Fe3+ and sodium thiosulfate at room...