基于水下电场测量的Ag/AgCl多孔电极性能研究

Performance of Ag/AgCl Porous Electrode Based on Marine Electric Field Measurement

摘要:

利用固相反应球磨法以及不同的干燥法制备AgCl超微粉体，将其按一定比例与纳米Ag粉体均匀混合、造粒、压制成模并烧结，获得复合的Ag/AgCl 多孔电极。并利用SEM、XRD、电化学工作站和低噪声前置放大器自制电噪声测试装置，对其进行微观结构分析和各种电化学性能测试，讨论多孔性结构对电极的极化性能、电极极差、短期稳定性以及电化学噪声水平影响。结果表明：利用冷冻-干燥法所制备的AgCl 粉体分散性极好，大小均匀，所制备的复合Ag/AgCl结构呈多孔状，电极的交换电流密度大，不易极化；两电极一致性好，极差电位小，约为–0.2744 mV；电极具有优良的短期稳定性，电极电势波动量不超过0.0477 mV/24 h，在低频段电极的自噪声降至纳伏级水平，为水下微伏级的微弱电场测试提供了极为有利的测试基础

Abstract:

The precursor powder of AgCl prepared by solid state reaction milling and different dry processes were mixed with Ag nanopowder in a certain ratio, prilled, pressed into a mold and then sintered, and finally a composite Ag/AgCl porous electrode was obtained. The electrode was characterized by SEM, XRD, electrochemical workstation and electrical noise test set. The influence of the porous structure of the electrode was discussed on the polarization properties, short-term stability and electrochemical noise. Results show that the precursor powder of AgCl prepared by freeze-drying method has excellent dispersivity and uniform size. The prepared composite Ag/AgCl electrode presents a porous structure with large exchange current density and good consistency. The potential difference of the two like electrodes is about –0.2744 mV. The electrode possesses good short term stability, with a potential difference drift less than 0.0477 mV/24 h. The voltage noise density of electrode is down to nV/Hz1/2 level at 1 Hz