Temperature tolerant new anhydrous Nafion-1,2,3-triazole blend membranes were prepared by room temperature (RT) and autoclave (AC) solution processing. Both blend membranes were very flexible and stable up to 260°C . Interestingly, they showed very different physico-chemical properties. In this paper, the properties of both the blend membranes were compared by Fourier transform infrared, thermogravimetric-differential thermal analysis, dynamic elastic modulus, X-ray diffraction, small angle X-ray scattering, atomic force microscopy, and proton conductivity. 1,2,3-Triazole was successfully incorporated into the nanostructure of Nafion. The blend membranes were more conductive than Nafion at 200°C under anhydrous conditions, and the conductivity was about 1mS∕cm . The blend membrane using AC solution processing showed higher thermal stability, density, and conductivity than that of RT solution processing. Therefore, an AC solution processing can be expected as a new synthesis method to get electrolyte membranes.

Power generation performance and long‐term durability of ammonia‐fueled solid oxide fuel cell (SOFC) systems are investigated with SOFC stacks consisting of 30 planar anode‐supported cells. SOFC systems with three different operation modes are employed: direct ammonia, external decomposition and autothermal decomposition. A novel BaO/Ni/Sm2O3/MgO catalyst is newly developed for the external ammonia cracker, whereas a Co‐Ce‐Zr composite oxide catalyst is used for the autothermal ammonia cracker. Initial performance measurement and 1,000 h long‐term durability test of the stacks are conducted. The stack fueled with direct ammonia achieves 1 kW power output with 52% direct current (DC) electrical efficiency; a slight decrease in its performance compared with the stack with the mixture fuel of hydrogen and nitrogen is attributed to the decrease in the stack temperature caused by the endothermic ammonia decomposition reaction. The external ammonia cracker helps to maintain the stack temperature, improving the initial performance of the stack. The stack performance with the autothermal ammonia cracker is also comparable to those with the other operation modes. It is also demonstrated that the stacks fueled with ammonia have excellent stability during the long‐term tests and 57% energy conversion efficiency at ca. 700 W electrical output is achieved with the external ammonia cracker.

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This paper was investigated for the properties of Nafion-1,2,3-triazole blend membranes by room temperature (RT) and autoclave (AC) solution processing with different weight percent. Both blend membranes were very flexible, transparent, and homogeneous. To get the high proton conductivity, it was required an AC solution processing at the temperature of 200oC. The conductivity of the blend membranes using AC was one order higher than that of RT solution processing. The elementary analysis of the blend membrane using AC solution processing showed higher hydrogen concentration than that of RT solution processing. 1H NMR of the blend solution using AC solution processing showed the chemical shifts of not only Nafion solution and 1,2,3-triazole but also new products. The Nafion-1,2,3-triazole blend membranes showed a thermal stability up to 200oC from cycle properties by differential scanning calorimetry (DSC).

Propyl-1,2,3-triazole was synthesized within the nanostructure of Nafion giving a Nafion – propyl-1,2,3-triazole composite, which was confirmed by IR and NMR. TEM images of the material revealed that the cluster structure of the composite membrane is smaller than that of Nafion. Analysis of the mechanical properties of the composite membrane showed that propyl-1,2,3-triazole might contribute to improve the strength of the network. A maximum conductivity of 0.07 S/cm and current density of 760 mA/cm2 at 0.6 V were obtained under cell conditions of 70°C, RH = 100%.