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To prepare excellent performance Ag/AgCl solid electrode as the goal, with solid-phase ball milling five hours and freeze-dried obtained AgCl powder as a raw material, then mixed it with silver powder, dry pressed and under liquid-phase sintered, solid-state Ag/AgCl electrode was prepared. Study the effect of the preparation process (included the milling time, forming pressure, sintering temperature) and the use of environment on the electrode’s microstructure, phase structure, density and electroche- mical properties. By means of SEM, XRD, DTA-TG, the electrode potential and self-noise analysis tested the main performance of Ag/AgCl electrode. Search the law between technology and performance to obtain the best Ag/AgCl electrode.The results showed that: To make electrode density, uniformity, and sintering full need pressure 30 tons and holding 4 minutes, sintering at 460℃keeping 90mins. Inap- proriate sintering temperature and holding time will make a variety of defects, even destruct the electrode, cut down the performance. Appropriate heating and cooling system can improve the density, refine grain. In addition, the sample photos and SEM analysis also found that: low pressure and too short holding time are prone to make porosity electrode, this would be inappropriate for the stability of electrode potential and self-noise.Finally, under the mechanism of electrode potential and stability with Nernst equ- ation analyse the effect of temperature and Cl- on the electrode electrochemical proper- ties, and test them by the measurement method that has developed in the paper. Results showed that the electrode can be used within a wider temperature range, the Cl- conce- ntration changed from 3% to 4% will impact the stability of electrode potential a little.The prepared electrode’s performance can meet requirements, the potential differ- ence is less than 1mV, 24 hours fluctuations within 0.1mV or less, after 15 days, the fluctuations still in the 0.1mV, the electrode noise in the low-frequency perform up to grade, to achieve nV level. Compared to other preparation process as the some areas, it has better performance.
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