Copper Electrolysis Research Articles

Electrolysis of copper in solid silicon

The diffusion of copper in silicon can be enhanced or retarded by application of an electric field. Transport measurements indicate that the copper diffuses with a single positive charge at temperatures around 1100°C. The amount of transport observed requires that a large fraction, possibly 50 per cent of the copper in solution, be positively charged and rapidly diffusing. On the basis of these results and the known slight electrical activity produced by copper in silicon at room temperature, we conclude that the charged, rapidly diffusing species of copper is interstitial. Similar experiments with Au and Fe in silicon show no field effect at 1100°C. It is found that copper in germanium diffuses rapidly with a positive charge at 700°C, in agreement with the results reported by F uller for higher temperatures.

EFFECT OF GELATIN ON THE CHANGES IN INITIAL CATHODE POLARIZATION DURING ELECTRODEPOSITION OF COPPER

In the absence of addition agent, the cathode polarization during initial electrolysis of copper from a solution of acid copper sulphate rose almost instantaneously from zero to approximately the steady state polarization. When gelatin was present in the electrolyte, the polarization generally increased to a maximum, Pmax, (in time tmax) then decreased to a minimum, Pmin, (in-time tmin) beyond which it increased to the steady state value, Ps. Generally, Pmax increased to a steady value with an increase in the time, T0, the electrode was in contact with the electrolyte before electrolysis was begun. At low, moderate, and high current densities respectively, tmax increased continuously, passed through a maximum, and decreased continuously with T0.The behavior of tmin approximately paralleled that of tmax. The polarization was linear in the logarithm of the current density; tmax and tmin decreased with increase in current density. The polarization values increased and tmax decreased, with increase in gelatin concentration. Increase of temperature had approximately the same effect as decrease in current density. With both chloride and gelatin present, Pmax was practically independent of T0 and chloride concentration, while Pmin and Ps showed minimum values at about 2 mgm./l. chloride.

Electrodeposition of Metal Powders

Metal powders may be produced electrolytically by two different methods: (a) direct deposition on the cathode, and (b) grinding of a brittle deposit. The principles underlying method (a) are dealt with in this paper. Three factors are shown to be responsible for the formation of powdery or spongy deposits: (1) low metal overvoltage, (2) depletion of the metal content of the cathode film, and (3) hydroxide formation in the cathode film. These factors may operate together or they may be operative under different conditions of electrolysis. Powder formation on the cathode in the electrolysis of copper, iron, nickel, zinc, and cadmium is described and analyzed.

Direct electrolysis of copper from silver chloride filtrates

The first page of this article is displayed as the abstract.

Publication announcement

IV. On Copper Electrolysis in Vacuo ” By William Gannon, M.A. Communicated by Professor Schuster, F. R. S. Received November 14, 1893. [Publication deferred.] V. ‘‘Note on the Action of Copper Sulphate and Sulphuric Acid on Metallic Copper.” By Arthur Schuster, F. R. S. Received November 14, 1893. [Publication deferred.] VI. “On a Chart of the Symmetrical Curves of the Three-Bar Motion.” By W. Brennand. Communicated by C. B. Clarke, F. R. S. Received November 17, 1893.

XXI. On the application of the electrolysis of copper to the measurement of electric currents

XXI. <i>On the application of the electrolysis of copper to the measurement of electric currents</i>

Electrolysis of Copper and Zinc

Electrolysis of Copper and Zinc