Self-Assembling Solid Oxide Fuel Cell Materials:  Mesoporous Yttria-Zirconia and Metal-Yttria-Zirconia Solid Solutions

Abstract

A new class of mesoporous (nickel/platinum)-yttria-zirconia materials, denoted meso-(Ni/Pt)YZ, which may have utility as electrode material in solid oxide fuel cells (SOFCs), have been synthesized by aqueous co-assembly of glycometalates and metal complexes with a surfactant template. These materials form as solid solutions with compositions that can be tuned over the range 12-56 atom % yttrium and 10-30 atom % nickel or 1-10 wt % platinum. The microstructure of the channel wall is nanocrystalline yttria-zirconia (YZ) and nickel/platinum is incorporated as metal oxide/metal clusters with diameters comparable to the size of the pores depending on the degree of loading of the metal precursor. Calcination in air of as-synthesized meso-(Ni/Pt)YZ materials causes the channel walls to crystallize and thicken as the imbibed organics are lost. It is the relatively thick, YZ nanocrystalline walls which are believed to be responsible for the impressive 800 °C thermal stability of meso-(Ni/Pt)YZ. This new class of binary and ternary mesoporous materials display the highest recorded surface area of any known form of (metal)-yttria-stabilized-zirconia. A narrow mesopore size distribution, nanocrystalline channel walls, and high thermal stability may lead to significant improvements in fuel/oxidant mass transport, oxide ion mobility, electronic conductivity, and charge transfer at the triplephase-boundary region of SOFC electrodes. It may also enable a reduction in the operating temperature of the SOFC.

Stabilization of mesoporous nanocrystalline zirconia with Laponite

“…ZrO 2 has attracted much attention because of its high performance as structural materials, electrode materials, electronics and oxygen sensors, supports and catalysts [1][2][3][4][5][6] . However, a major problem of this nonsiliceous oxide is its thermal stability.…”

“…Also, aliovalent and tetravalent dopants, such as Na + , Ca 2+ , Y 3+ , Si 4+ , Ce 4 , Th 4+ , etc. have been used to reinforce the nanocrystalline structures [15][16][17][18][19] . The stabilization was believed to be achieved by strong surface interaction between dopants ions and zirconia or by higher coordination number via addition of large size dopants.…”

Hydrothermal Synthesis, Characterization and Dielectric Properties of Zirconia Nanoparticles

“…The metal oxide nanoparticles have attracted special attention to design nano structures for a variety of applications because of their enhanced physical and chemical properties [1]. The oxide nanoparticles are used to design energy efficient lithium ion batteries [2,3], light emitting diodes [4,5], solar cells [6,7], fuel cells [8,9] and transistors [10,11], hydrogen storage devices [12,13], air purification [14], water purification [15], gas sensing [16], temperature and humidity sensing studies [17], drug delivery and bio imaging studies [18,19].…”

A robust NiO–Sm0.2Ce0.8O1.9 anode for direct-methane solid oxide fuel cell

“…Techniques including the hydroxide co-precipitation [21,22], urea-combustion [23], spray pyrolysis [24], self-assembling [25] and gel-casting methods [26] have been developed to synthesize NiO-SDC anodes with long TPB and controllable microstructures.…”