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Coelectrodeposition of crystalline copper-manganese oxide containing CuMn2O4 spinel for high energy supercapacitor application

M Sheikhzadeh, S Sanjabi
Journal Papers , , {Pages }

Abstract

Electrochemical growth of two-dimensional tin nano-platelet as high-performance anode material in lithium-ion batteries

S Khabazian, S Sanjabi, Dino Tonti
Journal PapersJournal of Industrial and Engineering Chemistry , 2020 January 2, {Pages }

Abstract

A template free, single-step process is developed for fabrication two-dimensional tin nano-platelets by electrochemical deposition in the presence of Triton X100 (TX100). Electrochemical studies combined with structural characterization revealed that during electrodeposition, TX100 molecules adsorb preferentially on {022} planes of Sn and highly anisotropic growth promotes in [200] direction which results in the formation of platelet morphology. The deposited platelets exhibit a high aspect ratio of 30 (width to thickness) and thickness of 25 ? 5 nm that uniformly covered the substrate with a high platelet density of 9 ? 108 cm−2. The electrochemical performance of nano-platelets for lithium storage was studied in detail and c

Martensitic transformation in stoichiometric NiMn and Ni–Mn-X alloys: A first principles study

Masoud Rahbar Niazi, Sohrab Sanjabi, Yousef Jamali, Reza Miresmaeili
Journal PapersJournal of Alloys and Compounds , 2020 June 7, {Pages 155978 }

Abstract

The martensitic phase transformation in stoichiometric NiMn alloy and its shape memory effect is investigated using first principles method based on Density Functional Theory (DFT). The elastic properties of the B2 austenite and the L10 martensite phases were compared and the results indicated that the B2 phase has a low elastic shear modulus along the [110] direction giving rise to the formation of L10. Electronic density of states (DOS) calculations showed that the existence of the pseudo-gap appearing at the Fermi level which stabilizes the martensite phase against the austenite depends on both magnetism and the tetragonality ratio. Using geometrically nonlinear theory of martensite it was found that large volume change and twinning shea

ELECTROCATALYTIC ACTIVITY OF Ni–Mn–Sn ALLOY FOAMS FOR OXYGEN EVOLUTION REACTION (OER)

N Taherian, S Sanjabi
Journal Papers , , {Pages }

Abstract

Influence of Cu shell on the anomalous WC grain growth in Ni-base brazed cladding

A Salimi, S Sanjabi
Journal PapersSurface and Coatings Technology , 2019 January 2, {Pages }

Abstract

In vacuum infiltration of Ni-based self-fluxing alloy (NiCrBSi) cladding, reinforced with ultrafine WC particles with average particle size (APS) of 0.2–0.4 μm, several plate-like anomalous WC grains were observed with size of greater than 20 μm. To prevent this anomalous grain growth, Cu shells were coated on WC particles. The very low solid state solubility of WC in copper phase at high temperature can lead to no anomalous WC grain growth. Cu shell with a thickness about 30–50 nm was deposited by means of electroless plating on ultrafine WC particles. The microstructural features of Cu-coated carbides and the resultant brazed claddings were characterized by field emission scanning electron microscopy (FESEM) equipped with ener

Ab initio study of the effect of thickness and epitaxial strain on the magnetic structure of NiMn freestanding films

Masoud Rahbar Niazi, Sohrab Sanjabi, Yousef Jamali
Journal PapersPhysics Letters A , Volume 383 , Issue 14, 2019 May 9, {Pages 1660-1665 }

Abstract

The magnetic properties of tetragonal structure of stoichiometric NiMn alloy is investigated using density functional theory within the local spin density approximation. The system studied here, is a free standing film. The effect of thickness and epitaxial strain on the magnetic and structural properties is examined. It is found that while the magnetic moments of Mn surface atoms vary depending on the number of layers being odd (3.60 μ B) or even (3.55 μ B) the magnitude of the magnetic moment for surface Ni atoms is constant (0.11 μ B). By applying epitaxial strain on the slabs, it was observed, for the first time, that the magnetic phase of NiMn films changes from “A-type-like” ferrimagnetic for compressive strains to “G-type-li

Activated Cu/Cu2O foam with Ni nanoparticles for electrocatalytic activity enhancement of hydrogen evolution reaction (HER) in acidic media

Nastaran Farahbakhsh, Sohrab Sanjabi
Journal PapersJournal of Industrial and Engineering Chemistry , Volume 70 , 2019 February 25, {Pages 211-225 }

Abstract

This paper presents the hydrogen evolution reaction of Cu/Cu2O foam by Ni nanoparticles, deposited by electrodeposition and electroless plating. The structure and morphology of Cu/Cu2O foam and deposited Ni nanoparticles were studied by FE-SEM and XRD. The foam with Ni nanoparticles had a high specific surface area measured by BET. The synthesized Cu/Cu2O foam/Ni electrode presented high electrocatalytic activity for HER, with low overpotential of −290?mV vs. Ag/AgCl and Tafel slope of 50?mV?decade−1. The stability study of the developed electrodes showed a high stability in short-term.

Electrocatalytic Activity of Ni-Mn-Sn Alloy Foams for Oxygen Evolution Reaction (OER)

Niloofar Taherian, Sohrab Sanjabi
Journal PapersSurface Review and Letters , 2019 May 29, {Pages }

Abstract

This study carried out to examine electrocatalytic activity of Ni-Mn-Sn alloy foams for oxygen evolution reaction (OER) in alkaline media. As the first step, Ni-Mn-Sn alloy foams were prepared of sulfate bath on copper substrate. Next, after optimization of electrodeposition condition by cyclic voltammetry (CV) test, foams were electrodeposited at different current densities 100, 120, 140 and 180 mA. cm-2. Then, they were characterized by field emission scanning electron microscopy (FE-SEM) along with energy disperse x-ray spectroscopy (EDS) to investigate surface morphologies and chemical compositions. According to FE-SEM results, it was revealed that formation of foam like structures were due to the presence of dynamic hydrogen bubbles te

Wear-resistant electrophoretic deposition (EPD) layer of titanium carbide

MR Gorji, S Sanjabi, C Edtmaier, C Katsich
Journal PapersJournal of Alloys and Compounds , Volume 806 , 2019 October 25, {Pages 1323-1338 }

Abstract

A wear-resistant EPD layer of TiCsub (i.e. sub micrometer titanium carbide) was synthesized by pressureless infiltration sintering. EPD is an ideal technique to form a porous layer that could be thickness modulated by easily change of applied voltage/current. Full melt spreading of NiCrBSiFe on TiCsub EPD layer and suppression of TiCsub grain growth can be achieved by substituting TiCsub with core-shell structure of NiP electroless plated on TiCsub. In an infiltrated layer, lowering of TiCsub pushing by solidification front hence homogeneous distribution of TiCsub along with eliminating porous TiCsub solid skeletons are essential factors to improve the wear properties. Wear measurement results showed decrement in friction coefficient of NiC

Photocatalytic H2 Evolution: Dealloying as Efficient Tool for the Fabrication of Rh‐decorated TiO2 Nanotubes

Mohsen Sheikhzadeh, Seyedsina Hejazi, Shiva Mohajernia, Ondrej Tomanec, Mohamed Mokhtar, Abdulmohsen Alshehri, Sohrab Sanjabi, Radek Zboril, Patrik Schmuki
Journal PapersChemCatChem , 2019 October 9, {Pages }

Abstract

In this work, we report on a facile and novel method for decorating titanium dioxide (TiO2) nanotubes with Rh nanoparticle‐nanonetworks that act as co‐catalysts in photocatalytic H2 generation. In a first step, a Ti−Rh (0.2 at%) alloy is etched in Kroll's solution leading to a dealloyed surface decorated with a Rh nanoparticle‐network of adjustable geometry and loading. By subsequent anodization of the alloy samples, Rh:TiO2 nanotubes can be grown where the tube mouths are strongly decorated with the Rh nanoparticle network (RhNw). As evident from X‐ray photoelectron spectroscopy (XPS) analysis, these Rh oxide Nws are converted to metallic Rh under UV irradiation. As a result, with time a steady increase of the H2 evolution fro

Combination of electrophoretic and electroless depositions to fabricate Ni/TiC cladding

MR Gorji, S Sanjabi, C Edtmaier
Journal PapersSurface Engineering , 2019 August 21, {Pages 07-Jan }

Abstract

A novel method is established that improves the shortcoming of embedding low volume fraction of reinforcements in Ni–P electroless coating. Experimental design of the present study is based on 5 steps: (1) electrophoretic deposition (EPD) of titanium carbide core inside the Ni–P shell particles (2) pre-sintering of as-EPD layer (3) electroless deposition of Ni–P top layer on as-EPD layer (4) heating the multilayer structure and (5) infiltration of the Ni–P melt phase through porous EPD layer. Anchoring TiC particles inside a Ni–P shell was done for catalyzing electroless Ni–P deposition on as-EPD layer and improving the high-temperature wettability of the EPD layer. By infiltration sintering on EPD layer (20 V for 2 min) a c

PHOTOCATALYTIC ACTIVITY AND WETTABILITY OF RGO/TiO2 NANOCOMPOSITES PREPARED BY ELECTROPHORETIC CO-DEPOSITION

E NOORMOHAMMADI, S SANJABI
Journal PapersSurface Review and Letters , 2019 June 20, {Pages 1950111 }

Abstract

Reduced graphene oxide (RGO)/TiO2 nanocomposite coating was synthesized using electrophoretic co-deposition (EPD) of graphene oxide and TiO2 colloidal suspension. Direct assembly by EPD facilitated the transformation from GO to RGO and resulted in RGO/TiO2 films on Cu substrate. The prepared samples were characterized by X-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy and Raman spectroscopy. The obtained results proved the presence of titania nanoparticles and RGO planes in the nanocomposite coatings and the reduction of GO during EPD process. Methylene blue photodegradation experiments showed that the degradation efficiency and the reduction rate of the contact angle increased in nano

Infiltration brazed core-shell WC@ NiP/NiCrBSi composite cladding

A Salimi, S Sanjabi
Journal PapersSurface and Coatings Technology , Volume 352 , 2018 October 25, {Pages 59-73 }

Abstract

In this study, a novel Ni-P-coated WC/NiCrBSi composite cladding was prepared on a carbon steel substrate through high-temperature vacuum brazing technique with the aim of improving the wear properties of the surface. In order to improve the wettability of WC particles by a liquid phase (NiCrBSi alloy), Ni-P layer was deposited on carbide particles by electroless plating. This layer assisted to fabricate a thick coating with very low porosity, improving adhesion strength between ceramic particles and the matrix. The morphology, crystal structure and microstructure of coated carbides and the resultant composite cladding were characterized by field emission scanning electron microscopy (FESEM) equipped with energy dispersive X-ray spectroscop

Nano composite foam layer of CuO/graphene oxide (GO) for high performance supercapacitor

M Sheikhzadeh, S Sanjabi, M Gorji, S Khabazian
Journal PapersSynthetic Metals , Volume 244 , 2018 October 31, {Pages 14-Oct }

Abstract

In this study, a facile and reproducible method has been developed to synthesize a nano composite foam layer of CuO/graphene oxide (GO) intended for supercapacitor applications. GO particles were deposited on elecroplated CuO foam layers through electrophoretic deposition (EPD). The results showed that by varying EPD time (1, 3, 7 min), the degree of coverage of the foam layer with GO changes. This makes it feasible to manipulate the specific capacity of (C sp) CuO foam layers (238.3 Fg− 1). It was shown that the specific capacity of the foam layer has been improved by amounts of 72%, 49% and 40% for EPD time deposition of 1, 3 and 7 min of GO, respectively. The results suggest a new versatile design to enhance super capacity and energy s

Surface free energy of TiC layers deposited by electrophoretic deposition (EPD)

Mohammad Reza Gorji, Sohrab Sanjabi
Journal PapersAIP Conference Proceedings , Volume 1920 , Issue 1, 2018 January 10, {Pages 020006 }

Abstract

In this study porous structure coatings of bare TiC (i.e. ~ 20 nm, 0.7 ?m and 5/45 ?m) and core-shell structures of TiC/NiP synthesized through electroless plating were deposited by EPD. Room temperature surface free energy (i.e. γs) of TiC and TiC/NiP coatings were determined via measuring contact angles of distilled water and diiodemethane liquids. The effect of Ni-P shell on spreading behavior of pure copper on porous EPD structures was also investigated by high temperature wetting experiments. According to the results existence of a Ni-P layer around the TiC particles has led to roughness (i.e. at least 0.1 ?m), and porosity mean length (i.e. at least 1 ?m) increase. This might be related to various sizes of TiC agglomerates

Synthesis of Ni/TiC composite coating by infiltration sintering of electrophoretic deposited layers

MR Gorji, C Edtmaier, S Sanjabi
Journal PapersMaterials & Design , Volume 125 , 2017 July 5, {Pages 167-179 }

Abstract

In this study, electrophoretic deposition (EPD) was employed as a practical way to form porous structure of TiC-based layer. The porous medium was infiltrated successfully by a Ni-based melt phase at 1060??C to fabricate Ni/TiC composite coatings. It was revealed that EPD parameters such as voltage affect the volume fraction of TiC particles in the sintered layer. It was indicated that electroless deposition of Ni-P shell on TiC core particles before EPD was necessary to enhance the melt penetration into the TiC porous matrix and hence to densify the porous medium. Microstructure and phase characterization were studied by field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). The results showed that TiC particles

ELECTROPHORETIC DEPOSITION OF TIO2-MULTI-WALLED CARBON NANOTUBE COMPOSITE COATINGS: MORPHOLOGICAL STUDY

MS MAHMOUDI JOZEE, S SANJABI, O Mirzaee
Journal PapersIranian Journal of Materials Science and Engineering , Volume 13 , Issue 3, 2016 September 15, {Pages 39-44 }

Abstract

Electrophorectic deposition (EPD) is a famous method to produce carbon nanotube ceramic nanocomposite coatings and films from powder suspensions 1. EPD is achieved via movement of charged particles in aqueous or organic suspensions and deposited onto an oppositely charged electrode under the action of an applied electric field. EPD can produce thin and nanostructure films on different and irregular shaped substrates with short deposition time, no required binder, easy control of coating thic ness, low cost and production of a film with high purity 1 2.TiO2 due to its high biocompatibility, chemical stability and thermal durability as well as high hardness and corrosion resistance, ma ing it a very attractive material

High corrosion resistance Ni-reduced graphene oxide nanocomposite coating

Seyed Ali Hosseini Khorasani, Sohrab Sanjabi
Journal PapersCorrosion Reviews , Volume 34 , Issue 06-May, 2016 December 1, {Pages 305-312 }

Abstract

This paper presents a high corrosion resistance Ni-graphene composite coating fabricated by co-electrodeposition on Cu substrate. First, GO was synthesized by improved Hummers’ method, and then different concentrations of GO aqueous solution were introduced to Ni Watt’s bath. During electrodeposition, GO and Ni ions were reduced simultaneously to form composite coating. The phase structure and morphology were covered by X-ray diffraction and scanning electron microscopy analysis, respectively. Atomic force microscopy (AFM) was employed to identify the surface topography of the coatings. Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and electrochemical impedance spectroscopy (EIS) were used to study the synthesis of

ELECTROPHORETIC DEPOSITION OF TiO2-MULTI-WALLED CARBON NANOTUBE COMPOSITE COATINGS: MORPHOLOGICAL STUDY

M Jozee, Saadat Mahmoudi, S Sanjabi, O Mirzaee
Journal PapersIRANIAN JOURNAL OF MATERIALS SCIENCE AND ENGINEERING , Volume 13 , Issue 3, 2016 September 1, {Pages 39-44 }

Abstract

A homogenous TiO2/multi-walled carbon nanotubes(MWCNTs) composite film were prepared by electrophoretic co-deposition from organic suspension on a stainless steel substrate. In this study, MWCNTs was incorporated to the coating because of their long structure and their capability to he functionalized by different inorganic groups on the surface. FTIR spectroscopy showed the existence of carboxylic groups on the modified carbon nanotuhes surface. The effect of applied electrical fields, deposition time and concentration of nanoparticulates on coatings morphology were investigated by scanning electron microscopy. It was found that combination of MWCNTs within TiO2 matrix eliminating micro cracks presented on TiO2 coating. Also, by increasing

ELECTROPHORETIC DEPOSITION OF TIO2-MULTI-WALLED CARBON NANOTUBE COMPOSITE COATINGS: MORPHOLOGICAL STUDY

JOZEE MS MAHMOUDI, S SANJABI, O Mirzaee
Journal Papers , Volume 13 , Issue 3, 2016 January 1, {Pages 39-44 }

Abstract

A homogenous TiO 2/multi-walled carbon nanotubes (MWCNTs) composite film were prepared by electrophoretic co-deposition from organic suspension on a stainless steel substrate. In this study, MWCNTs was incorporated to the coating because of their long structure and their capability to be functionalized by different inorganic groups on the surface. FTIR spectroscopy showed the existence of carboxylic groups on the modified carbon nanotubes surface. The effect of applied electrical fields, deposition time and concentration of nanoparticulates on coatings morphology were investigated by scanning electron microscopy. It was found that combination of MWCNTs within TiO 2 matrix eliminating micro cracks presented on TiO 2 coating. Also, by increas

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