摘要：

Stationary voltamperometric curves for halogen reduction at a polished platinum electrode in protic solvents using the corresponding halide as supporting electrolyte exhibit a single wave with a well-defined diffusion plateau. The values of α, the coefficient of proportionality between the limiting current and the halogen concentration, is shown to be constant, whatever the concentration range from 10 9 to 10 4 M; α is also independent of the halide concentration. It is inferred that the limiting current corresponds to the reduction of the various halogen species present in solution: free halogen, hypohalogenous entities, HOX or ROX, resulting from the reaction of halogen with the solvent, and trihalide ions X 3 from their reaction with halides. An amperometric set-up involving a highly sensitive detector and compensation of eddy currents is designed to determine very low halogen concentrations (10 810 9 M). This method is applied to the measurement of the yield in non-quantitative halide electrolysis.

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