Triethylamine sensing with a mixed potential sensor based on Ce0.8Gd0.2O1.95 solid electrolyte and La1-xSrxMnO3 (x = 0.1, 0.2, 0.3) sensing electrodes

Abstract

In this article, Ce0.8Gd0.2O1.95-based mixed potential type sensors attached with La1-xSrxMnO3 (x = 0.1, 0.2, 0.3) were fabricated to detect triethylamine (TEA). The effects of different ratios Sr2+ on the performance of triethylamine sensors were studied, and results showed that La0.8Sr0.2MnO3 had the best electrochemical catalytic activity to triethylamine, which could be proved by polarization curve and complex impedance curve. The sensor based on La0.8Sr0.2MnO3 sensing electrode had the highest response value (−113 mV) towards 100 ppm triethylamine. The optimum working temperature of the sensor was 580 °C. The low detection limit was 1 ppm, and the response value to 1 ppm triethylamine was −8 mV. At the range of 1-100 ppm triethylamine, the sensitivity of the sensor based on La0.8Sr0.2MnO3 sensing electrode was -59.2 mV/decade. In addition, the sensor also displayed excellent repeatability, stability during 30-day test and low cross-sensitivities towards interfering gases, e.g. methanol, methanal, acetone, ethanol and N-butanol. On the basis of the above research, the presented sensor can be considered as a potential sensor for monitoring triethylamine concentration in the atmospheric environment and microenvironment, and determining the freshness of fish.