Preparation And Application Of Composite Membrane Ag/AgCl Reference Electrode For Ocean Exploration

The bottom of the sea area has abundant natural resources,which play an important role in people's lives and the social sustainable development in the future.In the Marine environment monitoring and resource exploration,electrochemical sensor is indispensable.The reference electrode plays an important role in it.Therefore,a stable and reliable reference electrode is particularly important.While the Ag/AgCl electrode is recognized as the most ideal reference electrode in the application of seawater.The commercial Ag/AgCl glass electrode cannot be available in seawater because of fragile,affected by S2-,Br-and low accuracy,especially in deep-sea environment.Given those,the solid state reference electrode has great practical significance.In this study,the Ag/AgCl composite film electrode was developed and conducted a series of tests.The results showed that the composite film reference electrode can work against the hydrothermal temperature environment and with a bit of precision.So composite film reference electrode can be used in the sea but not suitable in high concentration salt solution of deep-sea hydrothermal solution.The Ag/AgCl bare electrode was prepared by electrolysis,and the Go-Nafion was deposited on bare AgCI to to protect the electrode.Then,the electrode was treated under the atmosphere in the furnace.The composite membrane electrode will be activated in the solution of 3.5%NaCl.After response test,long-term stability test,different pH solution test and foreign ion test of the electrodes,the results showed that the preparation of Ag/AgCl composite film electrodes potential can be stabilized at around 52±1mV(VS commercial saturated Ag/AgCl reference electrode)with electric potential drift in 1 mV when dipped in simulated seawater for 30h.Under the condition of low concentration of Br-and S2-,the electrode potential remained unchanged.And the composite membrane electrode can be as a reference electrode in the thermal environment under 150? with less potential shift.In addition,the prepared Ag/AgCl composite film electrode worked with a hydrothermal treatment Ir/IrOx pH electrode as a pH sensor in the 1.68?12.47 series of pH buffer test at room temperature,which showed a good Nernst response.At the same time,Pt electrode was used as the counter reference electrode to check the composite film electrode under the condition of 150?and after high temperature test the composite film electrode also be tested with commercial saturation reference electrode at room temperature,which showed that the membrane reference electrode has good resistance to high temperature performance.The prepared Go-Nafion composite membrane reference electrode can be used not only in the Marine environment,can also be used in deep-sea hydrothermal at low temperature.