Design of High-Performance Environmental Gas Sensors Using Solid Electrolytes and Multi-Component Auxiliary Electrodes

采用固体电解质和多组分辅助电极的高性能环境气体传感器的设计

基本信息

批准号：
03453090
负责人：
YAMAZOE Noboru
金额：
$ 4.67万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1992
项目状态：
已结题

项目摘要

Sensing properties of solid electrolyte oxygenic gas sensor were greatly improved by using multi-component auxiliary electrode. 1. The use of a binary nitrate electrode of NaNO_3-Ba(NO_3)_2 for solid electrolyte NO_2 sensor made it possible to stand operation at higher temperature up to 500ﾟC,as well as to suppress the interference of water vapor. An NO_2 sensor using Ba(NO_3)_2 auxiliary electrode and Ba-beta/beta"-alumina was found to show quicker responses and to stand higher temperature operation. A NASICON-based solid electrolyte device fitted with an NaNO_2 auxiliary electrode showed excellent sensing characteristics to NO and NO_2 in air,i.e., the electromotive force (EMF) followed the Nernt's equation for 1 - 800 ppm NO and 0.1 - 200 ppm NO_2 at temperatures of 150-240ﾟC. The response of these sensors were found to be totally independent of coexisting oxygen. 2. A NASICON-based CO_2 sensor was greatly improved in response and water vapor-resistance by using binary carbonate ele … More ctrodes of Na_2CO_3-BCO_3(B=Ca,Sr,Ba). These sensors could respond very well to CO_2 in air over a wide temperature range of 270-600ﾟC. The CO_2 sensor was further improved in stability by using Li-based binary carbonate electrodes of Li_2CO_3-BCO_3(B=Ca,Sr,Ba). The sensor responses, EMF, to varying partial pressure of CO_2 were in accordance with a 2-electron reaction of CO_2, while the response to a fixed P_<CO2> was found to be almost independent of partial pressure of O_2 at temperatures above 450ﾟC, while at 305ﾟC and below, it dependent on P_<O2> in a manner similar to a 2- electron reaction of O_2. Thus, two-types of sensing electrode reactions including peroxycarbonate or peroxide were indicated to occur depending on working temperature. 3. Electrochemical cells using MgO-stabilized zirconia tube coated with metal sulphates were found to exhibit fairly good sensing properties to 20-200 ppm SO_2 in air at 650-800ﾟC. SO_x sensor using Li_2SO_4-CaSO_4-SiO_2 auxiliary electrode showed quicker response, 90% response and 90% recovery time to 20 ppm SO_2 at 650ﾟC were 10_s and 7 min, respectively. This sensor exhibits excellent selectivity and good stability in long-term operation. Less

采用多元辅助电极大大提高了固体电解质氧气传感器的传感性能：1.采用NaNO_3-Ba(NO_3)_2二元硝酸盐电极作为固体电解质NO_2传感器，使其能够在更高的温度下工作。使用Ba(NO_3)_2辅助电极和抑制水蒸气干扰的NO_2传感器。 Ba-β/β"-氧化铝表现出更快的响应速度并能承受更高的工作温度。装有NaNO_2辅助电极的基于NASICON的固体电解质器件对空气中的NO和NO_2表现出优异的传感特性，即电动势(EMF) 遵循 Nernt 方程，适用于 1 - 800 ppm NO 和 0.1 - 200 ppm NO_2，温度为150-240℃。发现这些传感器的响应完全独立于共存的氧气。 2. 通过使用二元碳酸盐电极，大大提高了基于 NASICON 的 CO_2 传感器的响应和耐水蒸气性。 BCO_3(B=Ca,Sr,Ba) 可以在很宽的温度范围内对空气中的 CO_2 做出很好的响应。采用Li_2CO_3-BCO_3(B=Ca,Sr,Ba)锂基二元碳酸盐电极提高了CO_2传感器的稳定性,传感器对CO_2分压的响应电动势为:根据 CO_2 的 2 电子反应，而对固定 P_<CO2> 的响应被发现在温度高于450°C，而在305°C及以下，它以类似于O_2的2电子反应的方式依赖于P_<O2>。因此，包括过氧碳酸盐或过氧化物在内的两种类型的传感电极反应被表明发生。 3. 使用涂有金属硫酸盐的 MgO 稳定氧化锆管的电化学电池被发现对 20-200 ppm 表现出相当好的传感性能。使用Li_2SO_4-CaSO_4-SiO_2辅助电极的SO_2在650-800℃下的空气中的SO_x传感器表现出更快的响应，在650℃下对20ppm SO_2的90%响应和90%恢复时间分别为10μs和7分钟。在长期运行中表现出优异的选择性和良好的稳定性。