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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...
Deposition of (Ti, Ru)O2 and (Ti, Ru, Ir)O2 oxide coatings prepared by sol–gel method on titanium
, Article Journal of Sol-Gel Science and Technology ; Volume 79, Issue 1 , 2016 , Pages 44-50 ; 09280707 (ISSN) ; Ghorbani, M ; Sharif University of Technology
Springer New York LLC
Abstract
Titanium anodes activated by noble metal oxides possess a wide range of advantages and applications. Actually, coating of titanium anodes by highly conductive oxides of noble metals (Ru, Ir) dramatically increases the lifetime of these anodes. In this study, the binary coating consisting of Ti and Ru and the ternary coating consisting of Ti, Ru and Ir were prepared through sol–gel method. After coating of the titanium substrate, the corrosion behavior of coatings was studied by anodic polarization and cyclic voltammetry tests. The lifetime of anodes was determined using accelerated corrosion test. The morphology of coatings was examined by field emission scanning electron microscopy and...
Alumina feeding system changes in aluminum electrochemical cell with d18 technology for energy efficiency (Case study: Almahdi-hormozal aluminum smelter)
, Article 147th Annual Meeting and Exhibition of the Minerals, Metals and Materials Society, TMS 2018, 11 March 2018 through 15 March 2018 ; Volume Part F12 , 2018 , Pages 721-728 ; 23671181 (ISSN); 9783319725253 (ISBN) ; Samimi, A ; Baharvand, B ; Sharif University of Technology
Springer International Publishing
2018
Abstract
Aluminum reduction cells have benefited from point feeding technology for a long time, but there are still smelters which are using the old technology of center break and center feed system. Due to several factors this system is no longer approved and there have been a few attempts worldwide to upgrade these cells so as to implement the newer technology by applying mechanical and automation changes. In this paper we will present an attempt which was made in order to retrofit a so-called center break cell to point feeder cell. The results show that this project has decreased the energy consumption and anode effect frequency. Furthermore, there has been a significant increase in current...
In vitro bioactivity and corrosion resistance enhancement of Ti-6Al-4V by highly ordered TiO 2 nanotube arrays
, Article Journal of the Australian Ceramic Society ; Volume 55, Issue 1 , 2019 , Pages 187-200 ; 25101560 (ISSN) ; Sukiman, N. L ; Bushroa, A. R ; Nasiri Tabrizi, B ; Dabbagh, A ; Abu Kasim, N. H ; Basirun, W. J ; Sharif University of Technology
Springer International Publishing
2019
Abstract
In the present study, the structural features, corrosion behavior, and in vitro bioactivity of TiO 2 nanotubular arrays coated on Ti–6Al–4V (Ti64) alloy were investigated. For this reason, Ti64 plates were anodized in an ammonium fluoride electrolyte dissolved in a 90:10 ethylene glycol and water solvent mixture at room temperature under a constant potential of 60 V for 1 h. Subsequently, the anodized specimens were annealed in an argon gas furnace at 500 and 700 °C for 1.5 h with a heating and cooling rate of 5 °C min −1 . From XRD analysis and Raman spectroscopy, a highly crystalline anatase phase with tetragonal symmetry was formed from the thermally induced crystallization at 500 °C....
Anodizing of titanium in NaOH solution and its corrosion resistance in PBS physiologic solution
, Article Scientia Iranica ; Volume 10, Issue 3 , 2003 , Pages 361-366 ; 10263098 (ISSN) ; Vaezi, M. R ; Sharif University of Technology
Sharif University of Technology
2003
Abstract
Titanium is a highly reactive metal with an inclination to compose with oxygen. In order to increase its corrosion resistance and application, therefore, a thin layer of titanium oxide is produced on the surface by chemical and electrochemical methods. In the present research, titanium has been anodized in 20 M of NaOH solution under potentiostatic conditions at constant voltages of 25 and 35 V. The microstructure of the anodic layers has been studied by the use of a Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD). The results indicated that the structure of the anodic layers is amorphous with low porosity and that thickness increases with an increase in anodizing voltage. The...
TiO2/nanoporous silicon hybrid contact for heterojunction crystalline solar cell
, Article RSC Advances ; Volume 6, Issue 60 , 2016 , Pages 55046-55053 ; 20462069 (ISSN) ; Razi Astaraei, F ; Mohammadpour, R ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
The conventional solar cell architectures include a p-n junction of c-Si sandwiched by rear and front contacts. The conventional approach features a complex as well as expensive procedure. Here, we propose a new architecture for p-n heterojunction solar cells prepared by a simple and cost-effective procedure. In this regard, (1) a silicon wafer underwent surface treatment through electrochemical anodization. To prepare a stick junction, (2) photoactive TiO2 nanoparticles were deposited over the porous layer by electrophoretic technique. Finally, (3) indium tin oxide (ITO) was sputtered. During the fabrication steps, we examined various anodization times ranging from 6 to 12 min to study the...
A non-catalytic vapor growth regime for organohalide perovskite nanowires using anodic aluminum oxide templates
, Article Nanoscale ; Volume 9, Issue 18 , 2017 , Pages 5828-5834 ; 20403364 (ISSN) ; Waleed, A ; Gu, L ; Zhang, D ; Tavakoli, R ; Lei, B ; Su, W ; Fang, F ; Fan, Z ; Sharif University of Technology
Royal Society of Chemistry
2017
Abstract
In this work, a novel and facile synthesis process to fabricate single crystalline organometal halide perovskite nanowires has been successfully developed. Nanowires were grown in a high density ordered array from metal nanoclusters inside anodic aluminum oxide templates using a non-catalytic chemical vapor deposition method. Specifically, perovskite NWs were grown as a result of the reaction between methylammonium iodide (MAI) and the Pb/Sn (Pb or Sn) metal in anodic aluminum oxide templates under optimal conditions. The characterization results show that there is a reaction zone at the interface between the perovskite material and metal, at the bottom of the anodic aluminum oxide...
An ultrathin amorphous defective co-doped hematite passivation layer derived via an in situ electrochemical method for durable photoelectrochemical water oxidation
, Article Journal of Materials Chemistry A ; Volume 10, Issue 31 , 2022 , Pages 16655-16665 ; 20507488 (ISSN) ; Qorbani, M ; Sabbah, A ; Quadir, S ; Huang, C. Y ; Chen, K. H ; Chen, L. C ; Naseri, N ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
Although hematite (i.e., α-Fe2O3) has been widely investigated in photoelectrochemical water oxidation studies due to its high theoretical photocurrent density, it still suffers from serious surface charge recombination and low photoelectrochemical stability. Here we report an in situ electrochemical method to form a uniform and ultrathin (i.e., 3-5 nm) passivation layer all over the pores of an optimized ∼3.2% Ti-doped α-Fe2O3 photoanode. We unveil the amorphous and defective nature of the in situ derived layer assigned to a high concentration of oxygen vacancies and intercalated potassium atoms there, i.e., the formation of Ti/K co-doped defective α-Fe2O3−x. Owing to the efficient...
Exhaustive denitrification via chlorine oxide radical reactions for urea based on a novel photoelectrochemical cell
, Article Water research ; Volume 170 , 2020 , Pages 115357- ; Zhang, Y ; Zhou, C ; Bai, J ; Chen, S ; Li, J ; Wang, J ; Guan, X ; Rahim, M ; Zhou, B ; Sharif University of Technology
NLM (Medline)
2020
Abstract
Urea is a major source of nitrogen pollution in domestic sewage and its denitrification is difficult since it is very likely to be converted into ammonia or nitrate instead of expected N2. Herein, we propose an exhaustive denitrification method for urea via the oxidation of amine/ammonia-N with chlorine oxide radical, which induced from a bi-functional RuO2//WO3 anode, and the highly selective reduction of nitrate-N on cathode in photoelectrochemical cell (PEC). Under illumination, the WO3 photoanode side promotes the quantities hydroxyl and reactive chlorine radical, and these radicals are immediately combined to stronger chlorine oxide radical by RuO2 side, which obviously enhances the...
Comparison of the corrosion resistance of alkaline- and acid-anodized titanium
, Article Materials Performance ; Volume 54, Issue 1 , 2015 , Pages 51-55 ; 00941492 (ISSN) ; Ghahramani, S ; Afshar, A ; Malekinejad, P ; Sharif University of Technology
National Assoc. of Corrosion Engineers International
2015
Abstract
The process of self-color anodizing of titanium is done in acidic and alkaline solutions, and anodic films of different colors are formed. Results of this work show that the corrosion rate of titanium decreased after the application of an anodizing layer
Effect of samarium oxide on the electrical conductivity of plasma-sprayed SOFC anodes
, Article JOM ; Volume 68, Issue 10 , 2016 , Pages 2569-2573 ; 10474838 (ISSN) ; Samadi, H ; Nemati, A ; Sharif University of Technology
Minerals, Metals and Materials Society
Abstract
Solid oxide fuel cells (SOFCs) are rapidly becoming recognized as a new alternative to traditional energy conversion systems because of their high energy efficiency. From an ecological perspective, this environmentally friendly technology, which produces clean energy, is likely to be implemented more frequently in the future. However, the current SOFC technology still cannot meet the demands of commercial applications due to temperature constraints and high cost. To develop a marketable SOFC, suppliers have tended to reduce the operating temperatures by a few hundred degrees. The overall trend for SOFC materials is to reduce their service temperature of electrolyte. Meanwhile, it is...
Loading drug on nanostructured Ti6Al4V-HA for implant applications
, Article International Journal of Engineering, Transactions B: Applications ; Volume 31, Issue 8 , 2018 , Pages 1159-1165 ; 1728144X (ISSN) ; Sadrnezhaad, S. K ; Sharif University of Technology
Materials and Energy Research Center
2018
Abstract
Arrayed Ti6Al4V nanotubes (TNT) coated with hydroxyapatite (HA) were synthesized via electrochemical anodization method. Paracetamol was loaded onto TNT-HA electrode. Effects of anodization, nanotube formation and hydroxyapatite deposition on sorption and release of the drug were investigated. Saturation time of paracetamol on the anodized samples was 30% shorter than the hydroxyapatite-coated samples. Release behavior of the loaded drug was studied by (a) plunging the probe into phosphate buffered saline (PBS), (b) sampling the drug-loaded PBS at different times and (c) analyzing the solution via ultraviolet-visible (UV-vis) spectroscopy. Results showed that HA electrodes hold higher...
A novel and cost-effective method for fabrication of a durable superhydrophobic aluminum surface with self-cleaning properties
, Article Nanotechnology ; Volume 31, Issue 46 , 2020 ; Taghvaei, E ; Moosavi, A ; Sharif University of Technology
IOP Publishing Ltd
2020
Abstract
A hierarchical superhydrophobic surface is prepared via a two-step boiling water immersion process and anodization of the treated aluminum substrate in a novel hydrophobic electrolyte of aluminum nitrate and stearic acid mixture at room temperature. The immersion time in boiling water had a significant influence on the morphology and durability of the sample. A pseudoboehmite coating is created on the aluminum surface during the boiling process, as revealed by the field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) spectrophotometer results. The energy-dispersive x-ray spectroscopy analysis confirmed the formation of hydrophobic coating surface after...
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...
Antimony doped SnO2 nanowire@C core–shell structure as a high-performance anode material for lithium-ion battery
, Article Nanotechnology ; Volume 32, Issue 28 , 2021 ; 09574484 (ISSN) ; Abolhassani, R ; Hosseini, M ; Akbarnejad, E ; Mojallal, M. H ; Ghasemi, S ; Mohajerzadeh, S ; Sanaee, Z ; Sharif University of Technology
IOP Publishing Ltd
2021
Abstract
SnO2 is considered as one of the high specific capacity anode materials for Lithium-ion batteries. However, the low electrical conductivity of SnO2 limits its applications. This manuscript reports a simple and efficient approach for the synthesis of Sb-doped SnO2 nanowires (NWs) core and carbon shell structure which effectively enhances the electrical conductivity and electrochemical performance of SnO2 nanostructures. Sb doping was performed during the vapor-liquid-solid synthesis of SnO2 NWs in a horizontal furnace. Subsequently, carbon nanolayer was coated on the NWs using the DC Plasma Enhanced Chemical Vapor Deposition approach. The carbon-coated shell improves the Solid-Electrolyte...
SnO2@a-Si core-shell nanowires on free-standing CNT paper as a thin and flexible Li-ion battery anode with high areal capacity
, Article Nanotechnology ; Volume 28, Issue 25 , 2017 ; 09574484 (ISSN) ; Sadati Faramarzi, M ; Abdollahi, A ; Ramzani, R ; Ghasemi, S ; Sanaee, Z ; Sharif University of Technology
Institute of Physics Publishing
2017
Abstract
Here, we report 3D hierarchical SnO2 nanowire (NW) core-amorphous silicon shell on free-standing carbon nanotube paper (SnO2@a-Si/CNT paper) as an effective anode for flexible lithium-ion battery (LIB) application. This binder-free electrode exhibits a high initial discharge capacity of 3020 mAh g-1 with a large reversible charge capacity of 1250 mAh g-1 at a current density of 250 mA g-1. Compared to other SnO2 NW or its core-shell nanostructured anodes, the fabricated SnO2@a-Si/CNT structure demonstrates an outstanding performance with high mass loading (∼5.9 mg cm-2), high areal capacity (∼5.2 mAh cm-2), and large volumetric capacity (∼1750 mAh cm-3) after 25 cycles. Due to the...
Electrophoretic encapsulation for slow release of vancomycin from perpendicular TiO2 nanotubes grown on Ti6Al4V electrodes
, Article Materials Research Express ; Volume 6, Issue 12 , 2019 ; 20531591 (ISSN) ; https://iopscience.iop.org/article/10.1088/2053-1591/ab6c98 ; Ahmadi Seyedkhani, S ; Sadrnezhaad, S. K ; Sharif University of Technology
Institute of Physics Publishing
2019
Abstract
Ordered perpendicular TiO2 nanotubes (TNT) with 405 to 952 nm length and 60 to 90 nm diameter were grown via 40 to 120 min anodization of Ti6Al4V flat substrates. The samples were called TNT-40, -60, -80, -100, and -120. Vancomycin was loaded on the bare and anodized electrodes by separate immersion and electrophoretic (EP) deposition procedures. EP loading resulted in storage capacity of 5221.86 μg cm-2 for TNT-80 which was much higher than 1036.75 μg cm-2 of immersed sample. Drug release comprised of three stages: (i) burst release (78% for the bare, and 23% for the TNT-80 sample), (ii) gradual transport (21% for the bare, and 64% for the TNT-80 sample), and (iii) equilibrium. Transfer...
Electrophoretic encapsulation for slow release of vancomycin from perpendicular TiO2 nanotubes grown on Ti6Al4V electrodes
, Article Materials Research Express ; Volume 6, Issue 12 , 2019 ; 20531591 (ISSN) ; Ahmadi Seyedkhani, S ; Sadrnezhaad, S. K ; Sharif University of Technology
Institute of Physics Publishing
2019
Abstract
Ordered perpendicular TiO2 nanotubes (TNT) with 405 to 952 nm length and 60 to 90 nm diameter were grown via 40 to 120 min anodization of Ti6Al4V flat substrates. The samples were called TNT-40, -60, -80, -100, and -120. Vancomycin was loaded on the bare and anodized electrodes by separate immersion and electrophoretic (EP) deposition procedures. EP loading resulted in storage capacity of 5221.86 μg cm-2 for TNT-80 which was much higher than 1036.75 μg cm-2 of immersed sample. Drug release comprised of three stages: (i) burst release (78% for the bare, and 23% for the TNT-80 sample), (ii) gradual transport (21% for the bare, and 64% for the TNT-80 sample), and (iii) equilibrium. Transfer...
Room temperature selective sensing of aligned Ni nanowires using impedance spectroscopy
, Article Materials Research Express ; Volume 7, Issue 2 , 24 February , 2020 ; Fardindoost, S ; Iraji Zad, A ; Almasi Kashi, M ; Sharif University of Technology
Institute of Physics Publishing
2020
Abstract
Room temperature gas sensing behavior of arrayed one-dimensional (1D) nickel nanowires (Ni NWs) are investigated using impedance spectroscopy. Ni nanowires synthesized via electrochemical deposition method based on anodic aluminum oxide (AAO) templates. Their structural characterization verified by scanning electron microscopy (SEM), x-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) analysis. Impedance spectroscopy as an essential technique utilized to understand the mechanism of gas interaction with the wires through the changes in their electronic behavior. Bode and Nyquist plots with the real and imaginary impedances are plotted versus frequency range of 500 Hz...
Bioinspired TiO2/chitosan/HA coatings on Ti surfaces: Biomedical improvement by intermediate hierarchical films
, Article Biomedical Materials (Bristol) ; Volume 17, Issue 3 , 2022 ; 17486041 (ISSN) ; Ahmadi Seyedkhani, S ; Eslami Saed, A ; Sadrnezhaad, S. K ; Seza, A ; Sharif University of Technology
Institute of Physics
2022
Abstract
The most common reasons for hard-tissue implant failure are structural loosening and prosthetic infections. Hence, in this study, to overcome the first problem, different bioinspired coatings, including dual acid-etched, anodic TiO2 nanotubes array, anodic hierarchical titanium oxide (HO), micro- and nanostructured hydroxyapatite (HA) layers, and HA/chitosan (HA/CS) nanocomposite, were applied to the titanium alloy surfaces. X-ray diffraction and FTIR analysis demonstrated that the in situ HA/CS nanocomposite formed successfully. The MTT assay showed that all samples had excellent cell viability, with cell proliferation rates ranging from 120% to 150% after 10 days. The HO coating...