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The electrochemical effects of anisotropic lattice deformation during La0.6Sr0.4FeO3−δ growth by pulsed laser deposition are investigated by in situ impedance spectroscopy.

The oxygen exchange reaction mechanism on truly pristine surfaces of SOFC cathode materials (La0.6Sr0.4CoO3-δ, La0.6Sr0.4FeO3-δ, (La0.6Sr0.4)0.98Pt0.02FeO3-δ, SrTi0.3Fe0.7O3-δ, Pr0.1Ce0.9O2-δ and La0.8Sr0.2MnO3±δ) was investigated employing in-situ impedance spectroscopy during pulsed laser deposition (i-PLD) over a wide temperature and p(O2) range. Besides demonstrating the often astonishing catalytic capabilities of the materials, it is possible to discuss the oxygen exchange reaction mechanism based on experiments on clean surfaces unaltered by external degradation processes. All investigated materials with at least moderate ionic conductivity (i.e. all except LSM) exhibit polarization resistances with very similar p(O2)- and T-dependences, mostly differing only in absolute value. In combination with non-equilibrium measurements under polarization and defect chemical model calculations, these results elucidate several aspects of the oxygen exchange reaction mechanism and refine the understanding of the role oxygen vacancies and electronic charge carriers play in the oxygen exchange reaction. It was found that a major part of the effective activation energy of the surface exchange reaction, which is observed during equilibrium measurements, originates from thermally activated charge carrier concentrations. Electrode polarization was therefore used to control defect concentrations and to extract concentration amended activation energies, which prove to be drastically different for oxygen ncorporation and evolution (0.26 vs. 2.05 eV for LSF).

i-PLD measurements reveal beneficial effects of SrO at high temperatures and detrimental effects of CO2 adsorbates at low temperatures.

Collective intelligence (CI) captures a team’s ability to work together across a wide range of tasks and can vary significantly between teams. Extant work demonstrates that the level of collective attention a team develops has an important influence on its level of CI. An important question, then, is what enhances collective attention? Prior work demonstrates an association with team composition; here, we additionally examine the influence of team hierarchy and its interaction with team gender composition. To do so, we conduct an experiment with 584 individuals working in 146 teams in which we randomly assign each team to work in a stable, unstable, or unspecified hierarchical team structure and vary team gender composition. We examine how team structure leads to different behavioral manifestations of collective attention as evidenced in team speaking patterns. We find that a stable hierarchical structure increases more cooperative, synchronous speaking patterns but that unstable hierarchical structure and a lack of specified hierarchical structure both increase competitive, interruptive speaking patterns. Moreover, the effect of cooperative versus competitive speaking patterns on collective intelligence is moderated by the teams’ gender composition; majority female teams exhibit higher CI when their speaking patterns are more cooperative and synchronous, whereas all male teams exhibit higher CI when their speaking involves more competitive interruptions. We discuss the theoretical and practical implications of our findings for enhancing collective intelligence in organizational teams. Funding: This work was supported by the National Science Foundation [Grant VOSS-1322254], Division of Information and Intelligent Systems [Grant 1322241], Army Research Office [Grant W911NF-20-1-0006], Defense Advanced Research Projects Agency [Grant W911NF-20-1-0006], and Army Research Laboratory [Grant W911NF-19-2-0135]. Supplemental Material: The e-companion is available at https://doi.org/10.1287/orsc.2022.1602 .

Accelerating the oxygen reduction kinetics of solid oxide fuel cell (SOFC) cathodes is crucial to improve their efficiency and thus to provide the basis for an economically feasible application of intermediate temperature SOFCs. In this work, minor amounts of Pt were doped into lanthanum strontium ferrite (LSF) thin film electrodes to modulate the material's oxygen exchange performance. Surprisingly, Pt was found to be incorporated on the B-site of the perovskite electrode as non metallic Pt

The oxygen exchange reaction mechanism on truly pristine surfaces of SOFC cathode materials (La