Increased electrical conductivity and the mechanism of samarium‐doped ceria/Al₂O₃ nanocomposite electrolyte

Abstract

To further enhance the electrical conductivity of doped ceria, the samarium‐doped ceria (SDC)/Al2O3 nanocomposites were prepared through sintering the coprecipitated powders in 1100°C‐1300°C. The grain sizes of all composites are less than 100 nm and decrease with alumina addition. Besides the main phases of SDC and Al2O3, the SmAlO3 can precipitate in the composites if sintered at higher temperatures or for longer dwell time. The deviations of SDC diffraction peak positions demonstrate the solid solution of alumina into SDC lattice. The total electrical conductivities of the composites increase with alumina content until 30% alumina is added. The SDC/30%Al2O3 presents the higher total conductivity than the pure SDC by about five times. Specifically, the grain interior conductivity generally decreases with the alumina addition while the grain‐boundary conductivity increases with that. The introduction of the conductive SDC/Al2O3 interface can contribute to the rise of total conductivity, yet the excessive alumina addition also blocks the oxygen ion conduction. The SmAlO3 precipitation is detrimental to the ion conduction for it consumes part of alumina and leads to the decrement in Sm concentration of SDC grain. Appropriate alumina addition not only enhances the conductivity of SDC but also lowers the material cost.

A Collaborative Strategy for Boosting Lithium Storage Performance of Iron Phosphide by Fabricating Hollow Structure and Doping Cobalt Species

“…Compared with CoFeP, the discharge capacity of the FeP electrode decreases significantly from the first cycle, and the capacity is decreased to only 165.9 mA h g −1 after 87 cycles. The reason for the large difference in capacities for CoFeP and FeP is that the Co doping into FeP boosts the electronic conductivity of electrode, and the unique hollow structure affords more active sites and provides a faster kinetics . Figure b shows the rate capabilities of the FeP and CoFeP electrodes.…”

Synergetic enhancement of mechanical and electrical properties in Ce0.8Sm0.1Nd0.1O2−δ/La10Si6O27 composite electrolytes

“…21,22 Al 2 O 3 and MgO particles have been introduced into doped ceria electrolytes as the second phase to enhance the mechanical properties. 11,[23][24][25] A improvement in fracture toughness has been reported in 80% (Ce 0.8 Gd 0.2 )O 2Àd + 20%AlO 1.5 composite. 26 Whereas, the excessive addition of Al 2 O 3 and MgO exhibits a detrimental effect on the conductivity as they are blocking phases for oxygen ion conduction.…”

“…It is reported that the flexural strength and fracture toughness of CeO 2 are only about 100 and 1.5 MPa·m 1/2 , respectively, whereas the gadolinium‐doped ceria (GDC) shows an improved mechanical property, the flexural strength of 175 ± 10 MPa, and the fracture toughness (K IC ) of 1.75 ± 0.3 MPa·m 1/2 . Al 2 O 3 and MgO particles have been introduced into doped ceria electrolytes as the second phase to enhance the mechanical properties . A improvement in fracture toughness has been reported in 80% (Ce 0.8 Gd 0.2 )O 2−δ + 20%AlO 1.5 composite .…”

Ion-pair complex precursor approach to fabricate high surface area nanopowders of MgAl2O4 spinel

“…[3,4], transparent ceramics [5], humidity sensors [6], insulating materials in fusion reactors [7], dye adsorbents [8], luminescent hosts [9], ceramic ultrafiltration membranes [10], infrared window materials in optical devices [11] and catalyst support for n-butane dehydrogenation [12], oxidative dehydrogenation of ethane with CO 2 [13], methane oxidation [14], methane steam-reforming [15], ammonia decomposition [16], liquid phase citral hydrogenation [17], propane dehydrogenation [18], Methane decomposition [19], methane dry reforming [20], selective hydrogenation of acetylene [21], butane steam reforming [22] and autothermal reforming of methane [23]. MgAl 2 O 4 spinel was synthesized by metalechitosan complexation [1], hydrothermal [13], high-energy ball milling (mechanochemical synthesis) [2,24], solid state reaction (ceramic method) [2], co-precipitation [2,25], microwave-assisted combustion [26], solegel [27,28], organic precursor [28], combustion [28,29], surfactant assisted precipitation [30], modified solegel [31,32], spraydrying [33], freeze-drying [34], microwave-assisted solution combustion [35], normal micelle micro-emulsion …”