Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userSynthesis of Oxidation-Resistant Electrochemical-Active Copper Nanowires Using Phenylenediamine Isomers
237
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
Phenylenediamine (PDA) was chosen as a coordinating, reducing, and capping agent to effectively direct growth and protect against oxidation of Cu nanowires (Cu NWs) in an aqueous solution. PDA was found to reduce Cu (II) to Cu (I) at room temperature, and stabilize the resulting Cu (I) by forming a coordination complex. The presence of a stable Cu (I) complex is the key step in the synthesis of Cu NWs under mild conditions. Different PDA isomers lead to different growth paths of forming Cu NWs. Both pPDA and mPDA-synthesized Cu NWs were covered with a thin layer of polyphenylenediamine and show excellent anti-oxidation properties, even in the presence of water. The usefulness of the present and electrochemical active Cu NWs for a variety of nanotechnology applications is discussed.
rate research
Read More
Wear resistant coatings were produced on a permanent mould cast MRI 230D Mg alloy by (a) PEO in silicate based electrolyte, (b) PEO in phosphate based electrolyte, (c) hybrid coatings of silicate PEO followed by laser surface alloying (LSA) with Al and Al2O3, and (d) hybrid coatings of phosphate PEO followed by LSA with Al and Al2O3. Microstructural characterization of the coatings was carried out by scanning electron microscopy (SEM) and X(ray diffraction. The tribological behavior of the coatings was investigated under dry sliding condition using linearly reciprocating ball-on-flat wear test. Both the PEO coatings exhibited a friction coefficient of about 0.8 and hybrid coatings exhibited a value of about 0.5 against the AISI 52100 steel ball as the friction partner, which were slightly reduced with the increase in applied load. The PEO coatings sustained the test without failure at 2 N load but failed at 5 N load due to micro-fracture caused by high contact stresses. The hybrid coatings did not get completely worn off at 2 N load but were completely removed exposing the substrate at 5 N load. The PEO coatings exhibited better wear resistance than the hybrid coatings and silicate PEO coatings exhibited better wear resistance than the phosphate PEO coatings. Both the PEO coatings melted/decomposed on laser irradiation and all the hybrid coatings exhibited similar microstructure and wear behavior irrespective of the nature of the primary PEO coating or laser energies. SEM examination of worn surfaces indicated abrasive wear combined with adhesive wear for all the specimens. The surface of the ball exhibited a discontinuous transfer layer after the wear test.
We report on graphene-passivated ferromagnetic electrodes (GPFE) for spin devices. GPFE are shown to act as spin-polarized oxidation-resistant electrodes. The direct coating of nickel with few layer graphene through a readily scalable chemical vapour deposition (CVD) process allows the preservation of an unoxidized nickel surface upon air exposure. Fabrication and measurement of complete reference tunneling spin valve structures demonstrates that the GPFE is maintained as a spin polarizer and also that the presence of the graphene coating leads to a specific sign reversal of the magneto-resistance. Hence, this work highlights a novel oxidation-resistant spin source which further unlocks low cost wet chemistry processes for spintronics devices.
We present an electrochemical route for the integration of graphene with light sensitive copper-based alloys used in optoelectronic applications. Graphene grown using chemical vapor deposition (CVD) transferred to glass is found to be a robust substrate on which photoconductive Cu_{x}S films of 1-2 um thickness can be deposited. The effect of growth parameters on the morphology and photoconductivity of Cu_{x}S films is presented. Current-voltage characterization and photoconductivity decay experiments are performed with graphene as one contact and silver epoxy as the other.
We report a template-based in-situ electrochemical method for fabricating natural electric contacts on single nanowires using a pair of cross-patterned electrodes. Such electric contacts are highly stable upon thermal cycling between room temperature and milli-Kelvin temperatures. Direct imaging of the single-nanowire contacts using scanning electron microscopy is also demonstrated.
Nonylphenol ethoxylate (NPE 10) is a non ionic surfactant which is synthesized from alkylphenol ethoxylate. The accumulation of NPE-10 in wastewater will endanger the ecosystem as well as human being. At present, by an advancement of technology NPE 10 can be degraded indirectly by using an electrochemically treatment. Thus, this study aimed to evaluate the potential electrodegradation of NPE 10 by mediated electrochemical oxidation (MEO) using Ce(IV) ionic mediator. In addition, the influence of Ag(I) ionic catalyst in the performance of MEO for degradation of NPE 10 was also observed. The potency of MEO technology in degradation NPE 10 was evaluated by voltammetry technique and confirmed by titrimetry and LC-MS analyses. The results showed that in the absence of Ag(I) ionic catalyst, the degradation of NPE 10 by MEO was 85.93 %. Furthermore, when the Ag(I) ionic catalyst was applied, the performance of MEO in degradation of NPE 10 was improved to 95.12 %. The back titration using Ba(OH)2 confirmed the formation of CO2 by 46.79 %. Whereas the redox titration shows the total of degradation organic compounds by 42.50 %, which was emphasized by formation of two new peaks in LC-MS chromatogram. In summary, our results confirm the potential of MEO technology for NPE-10 degradation.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
