Selective catalytic reduction (SCR) utilizing urea hydrolysis to generate ammonia (NH 3 ) is the most efficient technology to reduce the emission of nitrogen oxides (NO x ). NH 3 detection is crucial in the closed-loop feedback system for the precise urea injection. In this work, a high-temperature NH 3 sensor using a BaZr 0.8 Y 0.2 O 3-δ (BZY) proton conductor as the electrolyte and a BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ (BCFZY) H + /e – /O 2– triple conductor as the sensing electrode (SE) is reported. The effect of the micromorphology of the BCFZY SE on the sensing performance is investigated by varying the sintering temperature of SE. The sensor shows high sensitivity to NH 3 with response currents of 0.39, 1.31, 3.03, and 1.81 μA/ppm at 350, 400, 450, and 500 °C, respectively. Furthermore, the sensor shows excellent selectivity and repeatability. This work demonstrates that the BCFZY based sensor has great potential for the high-temperature NH 3 detection.
Proton-conducting solid oxide fuel cells (H-SOFCs) demonstrate substantial potential for intermediate-to-low temperature operation due to the lower migration activation energy of protons (H + ) compared to oxygen ions (O 2− ). To address the critical role of cathode materials in determining cell performance, this study employs an A-site silver (Ag) doping strategy in perovskite oxide. BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ (BCFZY), Ba 0.95 Ag 0.05 Co 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ (BACFZY) and Ba 0.9 Ag 0.1 Co 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ (BACFZY-1) materials are all prepared using the sol-gel synthesis method. The investigation into the structure and element distribution of the synthesized materials reveals that BACFZY remains in a pure perovskite phase, with all elements evenly dispersed throughout. Ag-doped BACFZY surpasses BCFZY with greater electrical conductivity and thermal expansion compatibility. Moreover, the incorporation of Ag in BACFZY cathode facilitate the oxygen adsorption, leading to lower impedance and superior output performance with maximum peak power density of 1160 mW cm −2 at 650 °C. Meanwhile, The BACFZY cell maintained stable operation for 100 h. The aforementioned experimental findings indicate that the BACFZY material is a promising cathode for H-SOFC.
Protonic ceramic fuel cells (PCFCs) offer an efficient and low-emission power generation technology. The air electrode critically governs the oxygen reduction reaction (ORR) kinetics and overall cell efficiency of PCFCs. BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ (BCFZY) perovskite, a triple-conducting (H + /O 2− /e − ) air electrode material, enables superior ORR kinetics in PCFCs, yet its performance is limited by insufficient ionic conductivity. Here, we develop BaCo 0.4 Fe 0.4-x Zn x Zr 0.1 Y 0.1 O 3-δ (BCFZYZnx, x = 0, 0.1, 0.2) air electrodes via controlled Zn-for-Fe substitution to tailor metal-oxygen bonding. Experimental and theoretical analyses reveal that this chemical modification optimizes the electronic structure and enhances surface alkalinity, facilitating hydration and proton conduction. The PCFC incorporating BCFZYZn0.2 air electrode achieves a peak power density of 0.510 W cm −2 at 650°C—36% higher than pristine BCFZY—along with stable operation over 100 h. This study offers a simple and effective strategy for designing highly active and durable air electrodes for efficient oxygen reduction.
危险品化学品经营许可证（带存储）