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Abstract: The effects of MoO3 concentration on the sintering and electrical properties of Ce0.8Nd0.2O1.9 + 500 ppm SiO2 (NDCSi) and (Ce0.8Nd0.2O1.9)1 − x (MoO3) x  + 500 ppm SiO2 ( x = 0.01, 0.02, 0.03, 0.04, 0.05, NDCSi + 1MoO3, NDCSi + 2MoO3, NDCSi + 3MoO3, NDCSi + 4MoO3, NDCSi + 5MoO3) prepared through a modified sol–gel method were systematically investigated. The structures and ionic conductivities were characterized by XRD, FE-SEM and EIS. The results indicated a sharp increase in densification and conductivity for the system of NDCSi containing small amount of MoO3. It shows that NDCSi + 3MoO3 exhibited much higher relative density (RD = 96%), higher conductivity (σ t = 1.25 × 10−2 S cm−1 at 600 °C) and lower activation energy (E a = 0.81 eV) compared with NDCSi and the other MoO3 doped-NDCSi samples. Furthermore, MoO3 could be used as an effective sintering aid and a grain boundary scavenger for NDCSi system. And we obtained the optimal amount of the MoO3 is 3 mol%. [Copyright &y& Elsevier]

Abstract: The effect of small addition of different sintering aids (MoO3 and WO3) on the electrical properties of Ce0.9Nd0.1O2−δ has been investigated. The (Ce0.9Nd0.1)1−x M x O2−δ (x = 0.0; M = Mo, W, x = 0.01; Ce0.9Nd0.1O2−δ : NDC, (Ce0.9Nd0.1)0.99Mo0.01O2−δ : NDCMo; (Ce0.9Nd0.1)0.99W0.01O2−δ : NDCW) solid solutions were prepared and characterized. The X-ray diffraction patterns indicate that all the samples are single phases with a cubic fluorite structure. Moreover, from the field-emission scanning electron microscopy results, it is found (Ce0.9Nd0.1)0.99M0.01O2−δ (M = Mo, W) sintered at 1300 °C for 15 h have better sinterability than Ce0.9Nd0.1O2−δ . The total conductivity by electrochemical impedance spectroscopy are ranked as: NDCW  > NDCMo  > NDC measured at 700 °C, which is attributed to microstructures. It can be concluded that MoO3 and WO3 are both effective and WO3 seems to be more potential as sintering aids on the optimization of electrical properties for ceria-based electrolytes. [Copyright &y& Elsevier]

A novel Pr 2 NiO 4 (PNO)-Pr 0.2 Ce 0.8 O 1.9 (PCO) composite material was synthesized by typical solid state mixing and modified sol-gel method, and was assessed as a cathode material candidate for intermediate temperature solid oxide fuel cells (IT-SOFCs). The effects of different preparation methods on the microstructure, transport properties, and stability of electrode materials were systematically investigated. It was found that the introduction of PCO enhanced the electrochemical activity of PNO electrode. Among the composite materials, PNO–PCO composite cathode obtained by sol-gel method exhibited the best electrochemical performance. The polarization resistance (R P) on GDC electrolyte was 0.09 Ω cm2 at 800 °C. The NiO-GDC/GDC/PNO–PCO single cell yielded maximum output power of 0.57 W cm−2 at 800 °C. Furthermore, the R P exhibited an excellent stability after polarization for 120 h, indicating the good chemical compatibility of PNO–PCO composite cathode with other cell components. The desirable electrochemical properties and stability of PNO–PCO composite demonstrate its potential as a cathode material for IT-SOFCs. PNO–PCO composite was investigated as a promising cathode material for IT-SOFCs. PNO–PCO composite cathode prepared by sol-gel method exhibited low polarization resistance of 0.09 Ω cm2 at 800 °C, the electrolyte-supported single cell yielded a maximum power density of 0.57 W cm−2 at 800 °C. Image 1 • A novel PNO–PCO composite cathode is developed to act as cathode of SOFCs. • PCO exhibits excellent catalytic activity for cathodic ORR. • Composite prepared by sol-gel method has sufficient active sites for cathode ORR. • 46.2% improvement of power density with SGPP composite cathode. [ABSTRACT FROM AUTHOR]