Particle lithography has been extensively used as a robust and cost-effective method to produce large-area, close-packed arrays of nanometer scale features. Many technological applications, including biosensing, require instead non-close-packed patterns in order to avoid cross-talk between the features. We present a simple, scalable, single-step particle lithography process that employs colloidal self-assembly at liquid-liquid interfaces (SALI) to fabricate regular, open particle lithography masks, where the size of the features (40 to 500 nm) and their separation can be independently controlled between 3 and 10 particle diameters. Finally we show how the process can be practically employed to produce diverse biosensing structures.

The electrical conductivity of dense and nanoporous zirconia‐based thin films is compared to results obtained on bulk yttria stabilized zirconia (YSZ) ceramics. Different thin film preparation methods are used in order to vary grain size, grain shape, and porosity of the thin films. In porous films, a rather high conductivity is found at room temperature which decreases with increasing temperature to 120 °C. This conductivity is attributed to proton conduction along physisorbed water (Grotthuss mechanism) at the inner surfaces. It is highly dependent on the humidity of the surrounding atmosphere. At temperatures above 120 °C, the conductivity is thermally activated with activation energies between 0.4 and 1.1 eV. In this temperature regime the conduction is due to oxygen ions as well as protons. Proton conduction is caused by hydroxyl groups at the inner surface of the porous films. The effect vanishes above 400 °C, and pure oxygen ion conductivity with an activation energy of 0.9 to 1.3 eV prevails. The same behavior can also be observed in nanoporous bulk ceramic YSZ. In contrast to the nanoporous YSZ, fully dense nanocrystalline thin films only show oxygen ion conductivity, even down to 70 °C with an expected activation energy of 1.0 ± 0.1 eV. No proton conductivity through grain boundaries could be detected in these nanocrystalline, but dense thin films.

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La0.20Sr0.25Ca0.45TiO3 (LSCTA-) is a novel mixed ionic and electronic conductor (MIEC) material which can act as a potential replacement Solid Oxide Fuel Cell (SOFC) anode 'backbone' microstructure, for the current state-of-the-art Ni-based cermet. By impregnating this 'backbone' with electrocatalytically active coatings of metal oxides and metallic particles, it is possible to create high performance SOFC anodes which offer improved redox stability and tolerance to non-optimal fuel gases. Here, we present short-term test data for SOFC containing LSCTA-anode 'backbones' impregnated with a variety of catalyst systems including: Ni/CGO, Pd/CGO, Pt/CGO, Rh/CGO and Ru/CGO. Electrolyte-supported SOFC containing Ni/CGO impregnated anodes showed large reductions in Area Specific Resistance (ASR), in comparison to previous generation research (0.55 Ω cm 2 versus 1.2 Ω cm 2 , respectively). Exchange of the Ni component, for Pd and Rh, led to much lower ASR of 0.39 Ω cm 2 and 0.41 Ω cm 2 (in 97 % H2:3 % H2O, at 900 °C and 0.8 V), respectively. Equivalent circuit fitting of AC impedance spectra revealed the absence of an anode charge transfer process for the Rh/CGO catalyst system above 875 °C, in comparison to all other systems, identifying this system as a potential replacement for the Ni-based cermet.

Microstructures of yttria-stabilized zirconia (YSZ) thin fi lms deposited by spray pyrolysis at 370 ° C on sapphire are investigated. The as-deposited fi lms are predominantly amorphous and crystallize upon heating at temperatures above 370 ° C, developing grains in the range of 5 nm to several 100 nm. During post-deposition heat treatment up to 800 ° C, ∼ 50 vol% porosity develops in the center of the fi lms with gradients towards almost dense interfaces to the air and substrate. The reason for this porosity is the decomposition of residues from the precursor and the free volume liberated due to crystallization. Dense YSZ thin fi lms consisting of one monolayer of grains are obtained with annealing temperatures exceeding 1200 ° C. In gadoliniumdoped-ceria (CGO) thin fi lms similar microstructures and porosity are found after low-temperature heat treatments indicating that the precursor residues due to the deposition method are the main cause of the porosity. Grain growth stagnation in annealed thin fi lms is observed in both the YSZ and in CGO thin fi lms. Stagnating grain growth in the thin fi lms is rather caused by reduced grain boundary mobility, here predominately due to a "secondary phase", i.e., pores, than to other effects. The stagnation ceases at higher annealing temperatures after densifi cation has taken place.sapphire substrate and the obtained powder was measured in a Pt crucible up to 1300 ° C at 3 ° C min − 1 . Buoyancy and heat fl ow corrections were performed with the data from a second run using fully crystallized YSZ spray-pyrolyzed powder of the same mass.