RESUMO
A critical factor hampering the deployment of fuel-flexible, low-temperature solid oxide fuel cells (LT-SOFCs) is the long-term stability of the electrode in different gas environments. Specifically, for state-of-the-art Ni-cermet anodes, reduction/oxidation (redox) cycles during fuel-rich and fuel-starved conditions cause a huge volume change, eventually leading to cell failure. Here, we report a robust redox-stable SrFe0.2Co0.4Mo0.4O3 (SFCM)/Ce0.9Gd0.1O2 ceramic anode-supported LT-SOFC with high performance and remarkable redox stability. The anode-supported configuration tackles the high ohmic loss associated with conventional ceramic anodes, achieving a high open circuit voltage of â¼0.9 V and a peak power density of 500 mW/cm2 at 600 °C in hydrogen. In addition, ceramic anode-supported SOFCs are stable over tens of redox cycles under harsh operating conditions. Our study reveals that oxygen nonstoichiometry of SFCM compensates for the dimensional changes that occur during redox cycles. Our results demonstrate the potential of all ceramic cells for the next generation of LT-SOFCs.
RESUMO
Exploitation of alternative anode materials for low-temperature solid oxide fuel cells (LT-SOFCs, 350-650 °C) is technologically important but remains a major challenge. Here we report a potential ceramic anode Y0.7Ca0.3Cr1- xCu xO3-δ ( x = 0, 0.05, 0.12, and 0.20) (YCC) exhibiting relatively high conductivity at low temperatures (≤650 °C) in both fuel and oxidant gas conditions. Additionally, the newly developed composition (YCC12) is structurally stable in reducing and oxidizing gas conditions, indicating its suitability for SOFC anodes. The I- V characteristics and performance of the ceramic anode infiltrated with Ni-(Ce0.9Gd0.1O2-δ)(GDC) were determined using GDC/(La0.6Sr0.4CoO3-δ)(LSC)-based cathode supported SOFCs. High peak power densities of â¼1.2 W/cm2 (2.2A/cm2), 1 W/cm2 (2.0A/cm2), and 0.6 W/cm2 (1.3 A/cm2) were obtained at 600, 550, and 500 °C, respectively, in H2/3% H2O as fuel and air as oxidant. SOFCs showed excellent stability with a low degradation rate of 0.015 V kh-1 under 0.2 A/cm2. YCC-based ceramic anodes are therefore critical for the advancement of LT-SOFC technology.
RESUMO
In the title compound, (C(12)H(11)N(3))[SbCl(5)]·H(2)O, the Sb(III) centre is surrounded by five Cl atoms and displays a distorted square-pyramidal coordination geometry. The dihedral angle formed by the plane of the imidazole ring system with the pyridine ring is 4.380â (15)°. The crystal structure is stabilized by N-Hâ¯Cl, O-Hâ¯Cl and N-Hâ¯O hydrogen bonds, forming a three-dimensional network.
RESUMO
Two homochiral MOFs, (CBQ)CuI3(CN)3Br (1) and (CBC)CuI2.5(CN)2Br1.5 (2), were prepared by the solvothermal reaction of CuCN with N-4-cyanobenzyl quinidinium bromide (CBQ-Br) and N-4-cyanobenzylcinchonidinium bromide (CBC-Br). 1 and 2 are typical ferroelectric compounds while may have dipolar relaxation ferroelectrics and a high dielectric constant (epsilon o = 119.3).