MTECH EW-1000 – universal device for electrochemical research and analysis

The simple version of multyfunctional potentiostat-galvanostat MTech EW-1000 based on microcontroller ATmega8, extremely low-noise 24-bit analog-to-digital converter ADS1255 and 16 bit voltage output digital-to-analog converter AD5541 has been designed. Also we used REF3125 – precision (15 ppm/oC) voltage reference 2.5 V. The potentiostat-galvanostat controls the potential between the working electrode and the reference electrode in range ±5 V. The potentiostat-galvanostat has four ranges of measured current with programmed selecting from ±10 to ±1 A. The device can measure voltammograms under high sweep rate up to 500 mV/s. The device is equipped with RS232-USB converter based on CP2102 chip for communication with the computer through USB port. Computer program on Visual Basic 6 language for operating with potentiostat has been developed. This software allow to measure and visualize voltamperograms, chronopotentiograms, chronoamperograms, potentiometric and coulometric titration curves. For reduction of influence of electromagnetic noise and improvement signal/noise ratio the program makes digital processing of measured polarograms by Savitzky-Golay filter. Potentiostat-galvanostat MTech EW-1000 has been successfully tested on model systems using resistive electrochemical equivalents. Also, the main measuring techniques embedded in the device were tested using well-known analysis methods: coulometric titration of thiosulfate with electro-generated iodine and cyclic voltammetry of ferrocyanide/ferricyanide redox couple. Keywords : potentiostat, galvanostat, microcontroller, voltammetry, coulometric titration, MTech EW-1000.