The electrochemical performance of (La 0.8 Sr 0.2 ) x MnO 3 (x=1.0, 0.95, 0.9) electrodes with YSZ electrolyte has been investigated as a function of the A-site non-stoichiometry. The effect of cathodic bias on the electrode polarization resistance and the mechanism of oxygen reduction reaction have been studied. The passage of cathodic current leads to extensive impact to the LSM/YSZ interface microstructure and significantly enhances the electrochemical activity. LSM with different A-site nonstoichiometry also exhibits distinct activation behavior under cathodic bias. The final steady state performance of LSM electrode is determined by both of the polarization condition and the A-site non-stoichiometry. Under high current density (300mAcm -2 ), the stoichiometric LSM shows better performance than the A-site nonstoichiometric LSM electrodes, in contrast with the fact that it has the highest polarization resistance under OCV condition.

A bio-inspired surfactant was utilized to assist in the efficient impregnation of a nano-CeO2 catalyst throughout both porous Solid Oxide Fuel Cells (SOFC's) electrodes simultaneously. The process included the initial modification of electrode pore walls with a polydopamine film. The cell was then submersed into a cerium salt solution. The amount of nano-CeO2 deposited per impregnation step increased by 3.5 times by utilizing this two-step protocol in comparison to a conventional drip impregnation method. The impregnated cells exhibited a 20% higher power density than a baseline cell without the nano-catalyst at 750 o C (using humid H2 fuel).

A method for high resolution tactile sensing for robotic end-effectors used in variable environmental conditions is required for practical robotic applications, such as heavy industry, construction, military and space applications. In this work, a robust, flexible tactile sensor based on a capacitive sensing mechanism with high sensitivity and stability that can operate between −60 °C and 120 °C was developed. The active sensing thick film was composed of a 2:2 connective polymer-ceramic laminar composite. A stress-sensitive elastomer (Arathane 5753 A/B) was used as the primary compliant layer within the laminar architecture, and a HfO2 thin film was used as the dominating dielectric layer to improve the sensitivity of the sensor. The sensors were fabricated on a flexible polyimide film (Kapton) to conform to the end-effector geometry. The fabricated sensor showed good sensitivity and cycle stability (between 0 and 360 kPa). The capacitance change due to temperature variations were studied in detail. Three different capacitive sensor architectures were developed to study the influence of the HfO2 layer on the sensitivity of the sensor. Thermomechanical loading cycles were performed with in situ electrical acquisition to characterize the sensor. Chemical and structural characterization of the HfO2 layer deposited on a flexible substrate was implemented using conductive atomic force microscopy, Raman spectroscopy and x-ray photoelectron spectroscopy, and the optical properties were analyzed by the ultra-violet visible spectrophotometer.

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