1. E. Gorbova, A. Volkov, A. Chuikin, A. Efremov OBJECTIVES: 1.To study the characteristics of amperometric sensors, for measuring hydrogen content in humid nitrogen mixtures based on different proton conducting solid electrolytes, namely La 0.95 Sr 0.05 YO 3, CaTi 0.95 Sc 0.05 O 3 and CaZr 0.90 Sc 0.10 O 3. 2.To establish the influence of the sensor’s design on its own characteristics. 3.To investigate the influence of the temperature on hydrogen sensor’s characteristics. 4.To conclude about the suitability of different sensors for measuring hydrogen content in humid nitrogen mixtures. OBJECTIVES: 1.To study the characteristics of amperometric sensors, for measuring hydrogen content in humid nitrogen mixtures based on different proton conducting solid electrolytes, namely La 0.95 Sr 0.05 YO 3, CaTi 0.95 Sc 0.05 O 3 and CaZr 0.90 Sc 0.10 O 3. 2.To establish the influence of the sensor’s design on its own characteristics. 3.To investigate the influence of the temperature on hydrogen sensor’s characteristics. 4.To conclude about the suitability of different sensors for measuring hydrogen content in humid nitrogen mixtures. FIGURE 2. (a) Voltage-current curves of cell based on La 0.95 Sr 0.05 YO 3 at different high hydrogen content in the H 2 +2%H 2 O+N 2 mixture at 800ºC. (b) Dependence of the limiting current of cell based on La 0.95 Sr 0.05 YO 3 on hydrogen content H 2 +2%H 2 O+N 2 gas mixture at 750 mV. (b) (a) FIGURE 3. (a) Voltage-current curves of cell based on La 0.95 Sr 0.05 YO 3 at different low hydrogen content in the H 2 +2%H 2 O+N 2 mixture at 800ºC. (b) Dependence of the limiting current of cell based on La 0.95 Sr 0.05 YO 3 on hydrogen content H 2 +2%H 2 O+N 2 gas mixture. (a) (b) CONCLUSIONS 1.Development of promising amperometric hydrogen sensors based on proton conducting solid electrolytes for the analysis of H 2 +H 2 O+N 2 gas mixtures is realized. 2.Utilization of the solid electrolytes in the form of discs fixed all around by the sealant eliminates the use of capillary as a diffusion barrier and simplifies the sensor’s design. 3.Amperometric sensor’s operation at higher temperature values allows expanding the range of measured hydrogen concentrations. 4.A sensor based on La 0.95 Sr 0.05 YO 3 on with the porous diffusion barrier can be effective for the analysis of gas mixture with medium and high (up to 100%) hydrogen content, while a sensor based on CaZr 0.90 Sc 0.10 O 3 is suitable for the analysis of gas mixtures with low hydrogen content. 5.CaTi 0.95 Sc 0.05 O 3 is not suitable to be used as a hydrogen sensor. CONCLUSIONS 1.Development of promising amperometric hydrogen sensors based on proton conducting solid electrolytes for the analysis of H 2 +H 2 O+N 2 gas mixtures is realized. 2.Utilization of the solid electrolytes in the form of discs fixed all around by the sealant eliminates the use of capillary as a diffusion barrier and simplifies the sensor’s design. 3.Amperometric sensor’s operation at higher temperature values allows expanding the range of measured hydrogen concentrations. 4.A sensor based on La 0.95 Sr 0.05 YO 3 on with the porous diffusion barrier can be effective for the analysis of gas mixture with medium and high (up to 100%) hydrogen content, while a sensor based on CaZr 0.90 Sc 0.10 O 3 is suitable for the analysis of gas mixtures with low hydrogen content. 5.CaTi 0.95 Sc 0.05 O 3 is not suitable to be used as a hydrogen sensor. The authors of the present investigation are grateful to the Government of the Russian Federation for financial support (regulation 220, contract № 14.Z50.31.0001, March 24, 2014). FIGURE 4. Voltage-current curves of cell based on CaZr 0.90 Sc 0.10 O 3 in the gas mixture 1%H 2 +2%H 2 O+N 2 at various temperatures. INSTITUTE OF HIGH TEMPERATURE ELECTROCHEMISTRY of the Ural Branch of the Russian Academy of Sciences Laboratory of electrochemical devices based on solid oxide proton electrolytes H + LEDSOPE D H2 – diffusion coefficient of hydrogen, m 2 /s; S – cross-sectional area of the channel, m 2 ; P – the total pressure of environment, Pa; T – temperature, K; l – channel length, m. FIGURE 1. Amperometric sensor’s schematic representation: 1 – proton conducting electrolyte, 2 – sealant, 3 – internal electrode (anode), 4 – external electrode (cathode), 5 – current leads, 6 - diffusion capillary. Application of solid oxide proton electrolytes for amperometric sensors: analysis of hydrogen in H 2 +H 2 O+N 2 gas mixtures 1 2 3 4 5 6