基于聚二甲基硅氧烷胶与Zn-Al型水滑石复合膜为离子载体的溶解二氧化碳电极及其性能标定

CO2 microelectrode based on Zn-Al-LDH-ion carrier and its characterization

深海探测溶解CO2气体异常,可以为寻找热液口提供一个很好的证据。本文设计的基于自制的聚二甲基硅氧烷胶与Zn-Al型水滑石复合膜为离子载体的溶解CO2探测电极属于电势型CO2电极,适用于对深海中溶解形式的CO2的测量,具有体积微小、便于与pH、盐度、温度、氧化还原电位等多种传感器集成在同一探头腔内,实施在线探测等优点。实验室条件下,将该溶解CO2探测电极与银/氯化银参比电极分别接在Keithley 6517A高阻抗电位计输入端进行测试,测试结果表明:该电极对不同浓度的碳酸氢钠溶液具有良好的响应信号,响应时间大约在30s—1 min,检测限在10-1—10-4mol·L-1。

A good method to find hydrothermal vents is to detect the abnormal concentration of dissolved C02 in deep ocean. The authors have designed a dissolved C02 microelectrode based on polydimethylsiloxane （PDMS） gel and Zinc-Aluminium-hydrotalcite （Zn-Al-LDH） ion carrier complex membrane, which can be used to detect deep-ocean C02 abnormality. This dissolved C02 microelectrode is miniature, and can conveniently be integrated in the same probing cavity with pH mic sensor, oxidation-reduction potential sensor, etc. to detect various roelectrode, salinity meter, temperature in-situ signals. It has been tested in the laboratory condition, together with Ag/AgC1 reference microelectrode, connecting with the input of Keithley 6517A high-resistant potentiometer. It was shown that the signals responded well to different concentrations of NaHC03 solutions, with 30--60 second c.a. response time and a limiting range between 10-1 and 10-4 mol-L-1.