Electrocatalytic properties of the interfaces between La 0 8Sr0 2Ga0 8Mg0 115Co 0 085O3-δ (LSGMC) electrolyte and various cathodes: comprised of Sm0 5Sr0 5CoO3-δ (SSC), and La0 7Sr0 3Co0 2Fe0 8O 3-δ (LSCF) in composite forms (70wt.%) with LSGMC (30wt.%) were investigated under both oxygen reduction and evolution conditions. All the oxides were synthesized using the glycine-nitrate process (GNP). Symmetrical electrochemical cells were investigated with three-electrode linear dc polarization and ac impedance spectroscopy. For the composite SSC-LSGMC cathode/LSGMC interface, the cathodic overpotential under 1 A/cm2 current density was as low as 0.085 V at 700°C, 0.062V at 750°C and 0.051V at 800°C in air. Composite LSCF-LSGMC cathode/LSGMC interfaces were found to have about twice the exchange current density of composite SSC-LSGMC/LSGMC interfaces at 700°C © The Electrochemical Society.

This work reports the modified Pechini preparation and properties of an A-site deficient perovskite Sr0.86Y0.08TiO3-δ (SYT). Good chemical homogeneity and electrical conductivity were determined, making SYT a potential conductive component material in a composite anode for solid oxide fuel cells. As an oxide with inherent resistance to oxidation and hydroxylation, SYT could be a substitute for the metallic Ni component in composite anodes for solid oxide fuel cells, particularly for reversible solid oxide fuel cells with attendant high steam concentrations. © 2007 Elsevier B.V. All rights reserved.

As potential intermediate-temperature SOFC cathodes, perovskite composite cathode materials were evaluated in combination with a La0.8Sr 0.2Ga0.8Mg0.2O3-δ (LSGM) electrolyte. Various cathode materials La0.6Sr0.4Co 0.2Fe0.8O3-δ (LSCF), Ba 0.5Sr0.5Co0.8Fe0.2O 3-δ (BSCF), and Pr0.3Sr0.7Co 0.8Fe0.2O3-δ (PSCF) were compounded with La0.8Sr0.2Ga0.8Mg0.1Co 0.1O3-δ (LSGMC) as a mixed conducting composite element. All powders were synthesized by the glycine-nitrate process (GNP). XRD analysis found resistive phases of LaSrGaO4 and LaSrGa 3O7 present in the calcined layer of composite cathodes on LSGM. A bulk ohmie resistance of 3.81 Ω·cm2 and an interfacial resistance value of 0.16 Ω were measured for LSCF/LSGMC composite cathode on LSGM substrate at 800°C in air. Low-frequency secondary ares in the impedance spectra of LSCF/LSGMC cathode coupled with low current density and low cathode porosity suggested possible mass transfer limitations. The LSCF/LSGMC composite electrode performed best at 800°C (0.11 A/cm 2 at 0.045 V overpotential) while the BSCF/LSGMC performed best at the lowest temperature investigated (0.1 A/cm2 at 700°C and 0.04 V overpotential). ©The Electrochemical Society.

Four ceramic powders were produced using the glycine-nitrate process: lanthanum-doped barium cobaltite, ceria, magnesia, and strontium-doped lanthanum chromite (LSC). Glycine-to-nitrate ratios from 0.25 to 1 were investigated. During the combustion synthesis process, careful collection of process off-gas was followed by detailed gas analyses to determine product gas composition. All of the synthesis processes produced pure phase ceramic powders, but also produced criteria pollutant emissions levels that were significant enough (up to 4500 ppm of NO x and 9000 ppm of carbon monoxide) to warrant consideration. Equilibrium and chemical kinetic computations are used to determine the implications of the current findings. © 2007 The American Ceramic Society.

An all-perovskite-based intermediate-temperature fuel cell was fabricated from materials synthesized using glycine-nitrate process (GNP) combustion synthesis and modified Pechini synthesis routes. Yttrium-doped strontium titanate (SYT) was chosen as the conductive ceramic anode component to avoid problems associated with Ni-based anodes. La0.8 Sr0.2 Ga0.8 Mg0.1 Co0.1 O3-δ electrolyte-supported solid oxide fuel cells (SOFCs) with composite ceramic anode and cathode exhibit a relatively high power density of 0.246 Wcm at 800°C at 0.5 V. © 2007 The Electrochemical Society.

The global automotive industry sprayed over 2.6 billion liters of paint in 2018, much of which through electrostatic rotary bell atomization, a highly complex process involving the fluid mechanics of rapidly rotating thin films tearing apart into micrometer-thin filaments and droplets. Coating operations account for 65% of the energy usage in a typical automotive assembly plant, representing 10,000s of gigawatt-hours each year in the United States alone. Optimization of these processes would allow for improved robustness, reduced material waste, increased throughput, and significantly reduced energy usage. Here, we introduce a high-fidelity mathematical and algorithmic framework to analyze rotary bell atomization dynamics at industrially relevant conditions. Our approach couples laboratory experiment with the development of robust non-Newtonian fluid models; devises high-order accurate numerical methods to compute the coupled bell, paint, and gas dynamics; and efficiently exploits high-performance supercomputing architectures. These advances have yielded insight into key dynamics, including i) parametric trends in film, sheeting, and filament characteristics as a function of fluid rheology, delivery rates, and bell speed; ii) the impact of nonuniform film thicknesses on atomization performance; and iii) an understanding of spray composition via primary and secondary atomization. These findings result in coating design principles that are poised to improve energy- and cost-efficiency in a wide array of industrial and manufacturing settings.