Three-electrode electrochemistry dissolved oxygen sensor

The invention relates to the field of dissolved oxygen content detection, in particular to a three-electrode electrochemistry dissolved oxygen sensor. The sensor comprises a cylindrical shell of the sensor, a replaceable oxygen permeation membrane, a membrane cover, a gold electrode, a sliver electrode and a platinum electrode, wherein the gold electrode is arranged in the cavity of the cylindrical shell to serve as a working electrode, the sliver electrode serves as an auxiliary electrode, the platinum electrode serve as a sliver protection electrode, and the silver electrode, the gold electrode and the platinum electrode are independently connected with a polarization circuit through leads; the cavity of the cylindrical shell is full of a liquid reaction electrolyte, wherein the electrolyte reaction liquid comprises the following ingredients in parts by weight: 74.55 parts by weight of potassium chloride, 0.561 parts by weight of potassium hydroxide and 1000 parts by weight of water.By use of the electroche