Pulse polarography and electrochemical spectrum method for quick clearing double electric layer charging current error

Abstract

The invention provides a method of clear the error pulsepolargram and electrochemical spectrum of the two layer charging current. It relates to a new method in electrochemical analysing device and is applied to clearing error of the two layer charging current and solution ohm level drop with electrochemical instrument and electrochemical process detecting instrument. Current of high amplitude and narrow pulse is generated to provide ample two layer charging electrical quantity and two-layer charging toward the tested electrode to the level of the rectangle pulse of the driving signal. The tested electrode potential and command signal potenial are compared when the pulse current is interrupted, when the electrode potential reaches to the command potential and the two layer charging current is 0, the current flowing through the electrode is Faradic current,which make the electrode potential reach the driving signal potential exactly. Now, the two layer charging current is 0, the Faradic current sampling is quick and accurate, capable of measuring the overall curve in the second (subsecond) level.

Description

technical field [0001] The invention relates to a novel potential control method of an electrochemical detection and analysis device, in particular, it can be applied to an electrochemical analysis instrument or an electrochemical process detection instrument to quickly eliminate the electric double layer charging current error and the ohmic potential drop of a solution. Background technique [0002] Electrochemical analysis and detection has the advantages of sensitivity, low cost and easy to master, has become one of the commonly used analysis and detection methods in various fields, and has been widely used in environmental analysis, medical analysis, detection of living substances (such as dopamine, protein, etc.), food Testing and petrochemical testing. And there is development towards crossover technologies, such as electrochemical detectors coupled with liquid chromatography or capillary electrophoresis. Therefore, the application and market development prospects of ...

AI Technical Summary

Problems solved by technology

However, pulse polarography and square wave polarography still have serious limitations: since this method is based on the fact that the electric double layer charging current decays exponentially with time under square wave potential excitation, and the Faraday diffusion current decays exponentially with time. The square root method decays slowly, sampling at the moment when the electric double layer charging current decays to almost zero, in order to obtain a 'pure' Faraday current

However, due to the weak detection current of the microelectrodes and the high requirements for the corresponding electrical instruments, it is still difficult to meet the requirements of multi-dimensional separation and detection technology combined with fast chromatography and electrophoresis.

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