Fixedly-connected electrochemical sensor for measuring dissolved carbon dioxide and special sensing film thereof

The invention discloses a fixedly-connected electrochemical sensor for measuring dissolved carbon dioxide. The fixedly-connected electrochemical sensor comprises a conductive substrate and a sensing film, wherein the conductive substrate is a bottom layer, the sensing film is divided into an inner layer and an outer layer, the inner layer is a carbonate selective film, and the outer layer is a polymeric film. The invention also discloses a preparation method and application of the sensor. The partial pressure (P(CO2)) of dissolved carbon dioxide in a sample is directly calculated by utilizinga potential signal measured by a sensor. The whole operation process is simple and convenient, and gas does not need to be collected. And the potential signal measured by the sensor has good linear correlation with the partial pressure (P(CO2)) of dissolved carbon dioxide in the sample. And meanwhile, the accuracy of the electrode is still good in the presence of various interference factors. 本发明公开了一种测定溶解二氧化碳的固接电化学传感器，导电基