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Fabrication and Characterization of NiO-Based Electrocatalyst for Nitrogen Reduction Reaction (NRR): The Effects of Plasma Treatment on Surface Electrocatalytic Activity
, M.Sc. Thesis Sharif University of Technology ; Moshfegh, Alireza (Supervisor)
Abstract
Ammonia (NH3) is the second most synthesized chemical in the world which is used about 80% for the production of chemical fertilizers. Industrial production of ammonia commonly relies on Haber-Bosch method that is produced from gaseous N2 and H2, at very high pressure (200-400 atm) and high temperature (400-600oC) on the surface of an iron-based catalyst. But due to required high pressure and temperature researchers are looking for alternative methods that are environmentally friendly. In this research, we applied electrochemical nitrogen reduction reaction (NRR) used nickel oxide (NiO) deposited on nickel foam substrate by hydrothermal method. The prepared samples were treated by nitrogen...
Plasma surface functionalization of boron nitride nano-sheets
, Article Diamond and Related Materials ; Volume 77 , 2017 , Pages 110-115 ; 09259635 (ISSN) ; Achour, A ; Solaymani, S ; Islam, M ; Vizireanu, S ; Arman, A ; Ahmadpourian, A ; Dinescu, G ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
On silicon substrates, boron nitride nanosheets (BNNS) consisting of interconnected hexagonal boron nitride nano-layers were produced via chemical vapor deposition process at 1200 °C whose roughness's are at the micrometer- and nanometer-scale. The BNNS were functionalized in argon plasma admixed with ammonia or nitrogen or oxygen. The samples were characterized to investigate the surface chemistry and structural changes after plasma treatment using X-ray photoelectron spectroscope and Micro-Raman spectroscope techniques, respectively. While no significant changes in the surface features, upon plasma treatments of the BNNS, were noticed during SEM and TEM examination, the oxygen functional...
Investigation of metal absorption and antibacterial activity on cotton fabric modified by low temperature plasma
, Article Cellulose ; Volume 17, Issue 3 , 2010 , Pages 627-634 ; 09690239 (ISSN) ; Rashidi, A ; Ghoranneviss, M ; Anvari, A ; Rahimi, M. K ; Bameni Moghaddam, M ; Wiener, J ; Sharif University of Technology
2010
Abstract
In this work, the silver particle absorption and antibacterial activity of cotton fabric when modified by low temperature plasma were investigated. The modification consisted of plasma pre-functionalization followed by one-step wet treatment with silver nitrate solution. Oxygen and nitrogen were used as the working gases in the system, and the results were compared. The results showed that nitrogen plasma-treated samples can absorb more silver particles than oxygen-treated samples, and thus the antibacterial activity of the samples in this case, which was analyzed by the counting bacteria test, was increased considerably
Effect of low-frequency oxygen plasma on polysulfone membranes for CO 2/CH 4 Separation
, Article Journal of Applied Polymer Science ; Volume 124, Issue SUPPL. 1 , 2012 , Pages E199-E204 ; 00218995 (ISSN) ; Soltanieh, M ; Mousavi, S. A ; Shabani, I ; Sharif University of Technology
2012
Abstract
Low-frequency O 2 plasma was used to modify the surface of polysulfone gas-separation membranes. The effects of the treatment time and plasma power input on the membranes were also investigated. Pure CO 2 and CH 4 gas-permeation measurements were performed before and after plasma treatment. The results show the increase of permeability of the treated membranes due to surface ablation and surface polarization up to 5.63 and 68.80 gas-permeation units for CH 4 and CO 2, respectively, whereas, the CO 2/CH 4 selectivity of the treated membranes varied from 7.7 to 45.3, depending on the treatment conditions. Attenuated total reflection-Fourier transform infrared spectroscopy determined the...
Influence of plasma sputtering treatment on natural dyeing and antibacterial activity of wool fabrics
, Article Progress in Organic Coatings ; Volume 70, Issue 4 , 2011 , Pages 388-393 ; 03009440 (ISSN) ; Shahidi, S ; Anvari, A ; Motaghi, Z ; Wiener, J ; Šlamborová, I ; Sharif University of Technology
2011
Abstract
In this paper, the effect of plasma sputtering treatment on the natural dyeing properties of wool and the possibility of substituting it for mordant treatment have been studied. We used madder and weld as natural dyes and copper sulfate (CuSO4) as a metal mordant. We also used, copper as the electrode material, in a DC magnetron plasma sputtering device. The color strength of samples was analyzed using a Reflective Spectrophotometer and washing and light fastnesses were investigated according to I.S.O. standard recommendations. The results show that, the color strength and fastness of dyed wool samples have been improved after plasma treatment. The antibacterial counting test was also used...
Oxygen plasma-induced p-type doping improves performance and stability of PbS quantum dot solar cells
, Article ACS Applied Materials and Interfaces ; Volume 11, Issue 29 , 2019 , Pages 26047-26052 ; 19448244 (ISSN) ; Tavakoli, R ; Yadav, P ; Prochowicz, D ; Saliba, M ; Tavakoli, M. M ; Sharif University of Technology
American Chemical Society
2019
Abstract
PbS quantum dots (QDs) have been extensively studied for photovoltaic applications, thanks to their facile and low-cost fabrication processing and interesting physical properties such as size dependent and tunable band gap. However, the performance of PbS QD-based solar cells is highly sensitive to the humidity level in the ambient air, which is a serious obstacle toward its practical applications. Although it has been previously revealed that oxygen doping of the hole transporting layer can mitigate the cause of this issue, the suggested methods to recover the device performance are time-consuming and relatively costly. Here, we report a low-power oxygen plasma treatment as a rapid and...
Surface chemistry of atmospheric plasma modified polycarbonate substrates
, Article Applied Surface Science ; Volume 257, Issue 23 , September , 2011 , Pages 9836-9839 ; 01694332 (ISSN) ; Taghavinia, N ; Sharif University of Technology
2011
Abstract
Surface of polycarbonate substrates were activated by atmospheric plasma torch using different gas pressure, distance from the substrates, velocity of the torch and number of treatments. The modifications were analyzed by contact angle measurements, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and UV-vis spectrophotometry. Plasma treatment caused the surface characteristics to become more hydrophilic as measured by the water contact angle, which decreased from 88° to 18°. The decrease in contact angle was mainly due to oxidation of the surface groups, leading to formation of polar groups with hydrophilic property. XPS results showed an increase in the intensity of...
Efficient protein immobilization on polyethersolfone electrospun nanofibrous membrane via covalent binding for biosensing applications
, Article Materials Science and Engineering C ; Volume 58 , 2016 , Pages 586-594 ; 09284931 (ISSN) ; Soudi, S ; Soleimani, M ; Hosseinzadeh, S ; Esmaeili, E ; Vossoughi, M ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
In this paper we introduce novel strategy for antibody immobilization using high surface area electrospun nanofibrous membrane based on ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide (EDC/NHS) coupling chemistry. To present the high performance of proposed biosensors, anti-staphylococcus enterotoxin B (anti-SEB) was used as a model to demonstrate the utility of our proposed system. Polymer solution of polyethersolfone was used to fabricate fine nanofibrous membrane. Moreover, industrial polyvinylidene fluoride membrane and conventional microtiter plate were also used to compare the efficiency of antibody immobilization. Scanning electron microscopy images were taken to...
Cold atmospheric plasma modification and electrical conductivity induction in gelatin/polyvinylidene fluoride nanofibers for neural tissue engineering
, Article Artificial Organs ; Volume 46, Issue 8 , 2022 , Pages 1504-1521 ; 0160564X (ISSN) ; Hosseini, E ; Ramazani Saadatabadi, A ; Atyabi, S ; Bakhshandeh, H ; Mohamadali, M ; Aidun, A ; Farasati Far, B ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Background: This research follows some investigations through neural tissue engineering, including fabrication, surface treatment, and evaluation of novel self-stimuli conductive biocompatible and degradable nanocomposite scaffolds. Methods: Gelatin as a biobased material and polyvinylidene fluoride (PVDF) as a mechanical, electrical, and piezoelectric improvement agent were co-electrospun. In addition, polyaniline/graphene (PAG) nanoparticles were synthesized and added to gelatin solutions in different percentages to induce electrical conductivity. After obtaining optimum PAG percentage, cold atmospheric plasma (CAP) treatment was applied over the best samples by different plasma variable...