碳纤维电极具有成本低、化学稳定性好、性能可调控等优点,可用于开发高性能海洋电场传感器.利用电化学原位聚合法制备盐酸、硫酸、磷酸掺杂的聚苯胺/碳纤维(PANI/CF)复合电场电极,提高其电化学性能与电场响应性能.结果表明:碳纤维表面生成致密的导电聚苯胺膜,并在循环伏安测试中出现特征氧化还原峰;电化学阻抗分析显示PANI/CF复合电极低频(0.01 Hz)阻抗值至少降低为空白电极的1/118,利于对水下微弱电场信号进行响应.在电场响应性能测试中,盐酸掺杂PANI/CF复合电极电位漂移量最低达1.77 mV/d;能够较好地响应1 mV/10 mHz的低频率低强度电场信号;误差线性度最小值为0.111%,在同类电极中具有最好响应灵敏度.该新型复合电场电极制备方法简单、成本低廉,有助开发新一代低成本、高性能海洋电场传感器.

Carbon fiber electrode has the advantages of low cost, good chemical stability, and tunable performance, which can be utilized to develop high performance marine electric field sensors. Polyaniline/carbon fiber (PANI/CF) composite electrode doped with hydrochloric acid, sulfuric acid, and phosphoric acid are respectively fabricated by electrochemical in-situ polymerization, and their electrochemical performance and electric field response of the composite electrodes are studied respectively. The results show that conductive polyaniline film is uniformly formed on the surface of carbon fiber, and the characteristic redox peak occurs in the cyclic voltammetry test. Electrochemical impedance analysis shows that the low frequency (0.01 Hz) impedance of PANI/CF composite electrode decreases to at most 1/118 of that of the blank electrode, which is conducive to the quick response to weak underwater electric field signal. In the electric field response performance test, the potential drift of hydrochloric acid doped PANI/CF composite electrode is as low as 1.77 mV/d and it can better respond to 1 mV/10 mHz low-frequency and low-intensity electric field signal. It also has the minimum linearity error (0.111%), indicating the best response sensitivity among these modified electrodes. The preparation method of the composite electrode is simple and low-cost. Therefore, it is expected to be developed into a new generation of marine electric field sensor with low cost and high performance.