Elaboration of thin foils in copper and zinc by self-induced ion plating

The aim of this work was to determine the ability to produce thin metallic foils by self-induced ion plating. Foils of pure copper and pure zinc with a thickness of 35 μm have been successfully produced and their characteristics have been compared to foils obtained by conventional techniques (i.e. electroplating and rolling). Results show the following: (i) more or less compact microstructures can be obtained by self-induced ion plating depending on gas pressure and substrate temperature; (ii) microstructures obtained by self-induced ion plating are quite different from those obtained by electroplating and rolling; (iii) Young’s modulus depends on foils roughness; (iv) hardness depends on grain size by exhibiting a Hall-Petch behavior in the case of copper foils and an “inverse” Hall-Petch behavior in the case of zinc foils

Investigation of kilovolt ion sputtering second quarterly progress report

Kilovolt ion sputtering - electron beam focusing of cesium ion beam, radiation detection in copper atoms, ultrahigh vacuum system construction, and spectrometer pulse heigh

Improved solar cell contacting techniques Final report

Aluminum, nickel, and copper contacted solar cells using ion beam sputterin

Increased Cycling Efficiency and Rate Capability of Copper-coated Silicon Anodes in Lithium-ion Batteries

Cycling efficiency and rate capability of porous copper-coated, amorphous silicon thin-film negative electrodes are compared to equivalent silicon thin-film electrodes in lithium-ion batteries. The presence of a copper layer coated on the active material plays a beneficial role in increasing the cycling efficiency and the rate capability of silicon thin-film electrodes. Between 3C and C/8 discharge rates, the available cell energy decreased by 8% and 18% for 40 nm copper-coated silicon and equivalent silicon thin-film electrodes, respectively. Copper-coated silicon thin-film electrodes also show higher cycling efficiency, resulting in lower capacity fade, than equivalent silicon thin-film electrodes. We believe that copper appears to act as a glue that binds the electrode together and prevents the electronic isolation of silicon particles, thereby decreasing capacity loss. Rate capability decreases significantly at higher copper-coating thicknesses as the silicon active-material is not accessed, suggesting that the thickness and porosity of the copper coating need to be optimized for enhanced capacity retention and rate capability in this system.Comment: 15 pages, 6 figure

OPTIMIZATION OF SOLUTION POTENTIAL AND TEMPERATURE ON ION ELECTRODEPOSITION PROCESS OF COPPER (II) USING AN ADDITIVE OF FORMALDEHYDE

This research was conducted at the Chemical Research Laboratory of State University of Yogyakarta (UNY), Instruments Analysis Laboratory of Indonesian Islamic University (UII), and the Research Center for Physics of Indonesian Institute of Sciences (LIPI), Bandung. The purpose of this study was to determine the optimum solution potential and temperature on the electrodeposition process of Copper ion (II) using formaldehyde as an additive. The subject of this study was 400 ppm of copper solution. The object of this research was copper deposit on the cathode. Electrodeposition process used CuSO4 solution as a source of Cu ion (II), H2SO4 solution as supporting electrolyte, HNO3 solution as depolarizator, formaldehyde as an additive, and platinum plates as electrodes (cathode and anode). Electrodeposition process was done by potential variations of 2, 3, 4, 5 and 6 volts, the solution’s temperature variations of 27, 32, 37, 42 and 47°C and the deposition time of 25 minutes. Quantitative analysis was done by Atomic Absorption Spectrometry (AAS) to determine the concentration of Cu ion (II) after electrodeposition process. Qualitative analysis was by X-ray diffraction to determine crystal structures of Cu deposit of the electrodeposition on the optimum potential and temperature of the solution. The results showed that the optimum potential was 3 volts and the optimum temperature of the solution was 27°C. The concentration of Cu ion (II) of the electrodeposition on the solution’s optimum potential and temperature was 298.4750 ppm with the deposition efficiency of 25.38%. The crystal structure of Cu deposit of the electrodeposition on the solution’s optimum potential and temperature had a face-centered cubic system with a lattice parameter of 3.5877 A and the lattice planes of (111), (200), (220) and (311)

Copper Oxide Nanoparticles Impact Several Toxicological Endpoints and Cause Neurodegeneration in \u3cem\u3eCaenorhabditis elegans\u3c/em\u3e

Engineered nanoparticles are becoming increasingly incorporated into technology and consumer products. In 2014, over 300 tons of copper oxide nanoparticles were manufactured in the United States. The increased production of nanoparticles raises concerns regarding the potential introduction into the environment or human exposure. Copper oxide nanoparticles commonly release copper ions into solutions, which contribute to their toxicity. We quantified the inhibitory effects of both copper oxide nanoparticles and copper sulfate on C. elegans toxicological endpoints to elucidate their biological effects. Several toxicological endpoints were analyzed in C. elegans, including nematode reproduction, feeding behavior, and average body length. We examined three wild C. elegans isolates together with the Bristol N2 laboratory strain to explore the influence of different genotypic backgrounds on the physiological response to copper challenge. All strains exhibited greater sensitivity to copper oxide nanoparticles compared to copper sulfate, as indicated by reduction of average body length and feeding behavior. Reproduction was significantly reduced only at the highest copper dose, though still more pronounced with copper oxide nanoparticles compared to copper sulfate treatment. Furthermore, we investigated the effects of copper oxide nanoparticles and copper sulfate on neurons, cells with known vulnerability to heavy metal toxicity. Degeneration of dopaminergic neurons was observed in up to 10% of the population after copper oxide nanoparticle exposure. Additionally, mutants in the divalent-metal transporters, smf-1 or smf-2, showed increased tolerance to copper exposure, implicating both transporters in copper-induced neurodegeneration. These results highlight the complex nature of CuO nanoparticle toxicity, in which a nanoparticle-specific effect was observed in some traits (average body length, feeding behavior) and a copper ion specific effect was observed for other traits (neurodegeneration, response to stress)

Controlled Synthesis of Carbon-Encapsulated Copper Nanostructures by Using Smectite Clays as Nanotemplates

Rhomboidal and spherical metallic-copper nanostructures were encapsulated within well-formed graphitic shells by using a simple chemical method that involved the catalytic decomposition of acetylene over a copper catalyst that was supported on different smectite clays surfaces by ion-exchange. These metallic-copper nanostructures could be separated from the inorganic support and remained stable for months. The choice of the clay support influenced both the shape and the size of the synthesized Cu nanostructures. The synthesized materials and the supported catalysts from which they were produced were studied in detail by TEM and SEM, powder X-ray diffraction, thermal analysis, as well as by Raman and X-ray photoelectron spectroscopy.