固相法制备Bi_(4)V_(2)O_(11)固体电解质在NH_(3)传感器中的应用

Bi_(4)V_(2)O_(11)Solid Electrolyte for NH_(3) Sensor through Solid-state Reaction Method

通过固相反应法制备了在中低温下具有高离子导电性的固体电解质Bi_(4)V_(2)O_(11),并以CuV_(2)O_(6)为敏感电极组装成混合电位型NH_(3)传感器。通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS)分析了固体电解质的相组成和传感器的微观形貌。结果表明,在中低温(300℃~600℃)下Bi_(4)V_(2)O_(11)的电导率高于传统氧离子导体YSZ。传感器测试结果表明,基于Bi_(4)V_(2)O_(11)作固体电解质CuV_(2)O_(6)作敏感电极的传感器能在300℃~500℃的温度范围内对10 ppm~300 ppm的NH_(3)进行检测,而以YSZ作固体电解质的传感器在300℃~350℃性能下降明显;传感器在400℃下有着最高的灵敏度(-59.15 mV/decade),优于相同条件下以YSZ作固体电解质的传感器(-42.89 mV/decade)。传感器具有稳定的响应,传感器的响应值和NH_(3)浓度的对数值呈现良好的正比例关系。

Bi_(4)V_(2)O_(11)solid electrolyte,with high ionic conductivity at low and medium temperatures,was prepared by using solid-state reaction method,for application in a mixed-potential NH_(3)sensor using CuV_(2)O_(6)as the sensitive electrode.Phase composition microscopic morphology of the samples was analyzed by using X-ray diffractometry(XRD),scanning electron microscopy(SEM)and energy spectroscopy(EDS).The conductivity of Bi_(4)V_(2)O_(11)was higher than that of the conventional oxygen ion conductor YSZ at low and medium temperatures(300–600℃).The sensor,with Bi_(4)V_(2)O_(11)as the solid electrolyte and CuV_(2)O_(6)as the sensitive electrode,was capable of detecting 10–300 ppm NH_(3),in the temperature range of 300–500℃,while the sensor based on YSZ as solid electrolyte shows significant performance degradation in the temperature range of 300–350℃.The sensor has the highest sensitivity(−59.15 mV/decade)at 400℃,which is superior to the one based on YSZ as solid electrolyte under the same condition(−42.89 mV/decade).The sensor has a stable response,with the logarithmic values showing a good positive relationship.