Surface treatment of glassy carbon electrode

　　glassy carbon electrodeBefore using any solid electrode, its surface must be cleaned to remove contamination caused by impurities or impurities adsorbed on the surface. Just as most metal electrode surfaces are prone to the formation of oxide layers, the oxidation of carbon electrode surfaces can generate various oxygen-containing groups (such as alcohols, phenols, carboxyl groups, ketoquinones, and anhydrides), resulting in decreased reproducibility, stability, sensitivity, and loss of selectivity of the electrode.

During the experiment, a 3mm diameter glassy carbon electrode was first polished step by step with metallographic sandpaper (1 #~7 #), and then polished to a mirror finish on suede with Al2O3 slurry of 1.0 and 0.3 μ m, respectively,glassy carbon electrodeAfter each polishing, the surface dirt should be washed away first, and then transferred to an ultrasonic water bath for cleaning, 2-3 minutes each time, repeated three times, and finally cleaned with 1:1 ethanol, 1:1 HNO3, and distilled water by ultrasonic cleaning in sequence.

*After washing, the electrode should be activated by cyclic voltammetry in a 0.5-1mol/L H2SO4 solution, with a scanning range of 1.0-1.0V, and repeated scanning until a stable cyclic voltammetry is reached. Record the cyclic voltammetry curve of 1 × 10-3mol/L K3Fe (CN) 6 solution in 0.20mol/LKNO3 to test the electrode performance. The scanning speed is 50 mV/s and the scanning range is 0.6~-0.1V. The peak potential difference in the cyclic voltammetry obtained under laboratory conditions should be below 80mV and as close to 64mV as possible before the electrode can be used. Otherwise, the electrode needs to be reprocessed,glassy carbon electrodeUntil it meets the requirements.