The electrochemical reduction of CO2 to CH4 and C2H4 in aqueous alkaline solutions at Cu electrodes was studied under potentiostatic conditions at-2.00V vs. SCE. The current at the Cu electrodes and the rate of hydrocarbon formation were monitored as a function of time over a temperature range from 0 to 48~ Solutions of formate, formaldehyde, and methanol, possible intermediates in the reduction process, were also electrolyzed. Surface analyses (XPS and AES) were also performed on the Cu electrodes following electrolysis to identify surface intermediates. In addition to hydrocarbon formation, a poisoning process occurred, causing a deposit of a black film on the surface of the Cu cathode. XPS and AES studies indicated that the black film was graphitic carbon, probably the result of a side reaction, the reduction of CQ through formate to graphite. A tentative reaction mechanism for CO2 reduction, based upon the data here and those of previous investigators, involving the reaction path CO2-* CO ~ surface-bound formyl (Cu-HCO) ~ surface-bound methylene (Cu-CH2)-~ hydrocarbon products, is proposed.

No abstract

A new method for synthesizing (/z-C6H13)3SiO(SiPcO)2Si(n-C6H13)3 and methods for isolating («-C6H13)3SiO(SiPcO)3Si(n-C6H13)3 and (n-C6H13)3SiO(SiPcO)4Si(n-C6H13)3 from a mixture containing these two oligomers are described. Well-resolved NMR spectra of the three oligomers and of (n-C6H13)3SiOSiPcOSi(n-C6H13)3 are presented. Electrochemical studies of the series (n-C6H13)3SiO(SiPcO)"Si(«-C6H13)3 ( = 1-4) show n one-electron oxidation and n one-electron reduction waves and give evidence

No abstract