Cubic perovskite SrCoO3−δ was successfully prepared through simple anion F-doping and demonstrated great OER performance.

Driven by the demand to minimize fluctuation in common renewable energies, reversible solid oxide cells (RSOCs) have drawn increasing attention for they can operate either as fuel cells to produce electricity or as electrolysis cells to store electricity. Unfortunately, development of proton-conducting RSOCs (P-RSOCs) faces a major challenge of poor reliability because of the high content of steam involved in air electrode reactions, which could seriously decay the lifetime of air electrode materials. In this work, a very stable and efficient air electrode, SrEuFeCoO (SEFC) with layer structure, is designed and deployed in P-RSOCs. X-ray diffraction analysis and High-angle annular dark-filed scanning transmission electron microscopy images of SEFC reveal that Sr atoms occupy the center of perovskite slabs, whereas Eu atoms arrange orderly in the rock-salt layer. Such a special structure of SEFC largely depresses its Lewis basicity and therefore its reactivity with steam. Applying the SEFC air electrode, our button switches smoothly between both fuel cell and electrolysis cell (EC) modes with no obvious degradation over a 135 h long-term test under wet H (∼3% HO) and 10% HO-air atmospheres. A record of over 230 h is achieved in the long-term stability test in the EC mode, doubling the longest test that had been previously reported. Besides good stability, SEFC demonstrates great catalytic activity toward air electrode reactions when compared with traditional LaSrCoFeO air electrodes. This research highlights the potential of stable and efficient P-RSOCs as an important part in a sustainable new energy power system.

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Solid oxide fuel cells (SOFCs) can directly operate on hydrocarbon fuels such as natural gas; however, the widely used nickel-based anodes face grand challenges such as coking, sulfur poisoning, and redox instability. We report a novel double perovskite oxide Sr2Co0.4Fe1.2Mo0.4O6−δ (SCFM) that possesses excellent redox reversibility and can be used as both the cathode and the anode. When heat-treated at 900 °C in a reducing environment, double perovskite phase SCFM transforms into a composite of the Ruddlesden–Popper structured oxide Sr3Co0.1Fe1.3Mo0.6O7−δ (RP-SCFM) with the Co–Fe alloy nanoparticles homogeneously distributed on the surface of RP-SCFM. At 900 °C in an oxidizing atmosphere, the composite transforms back into the double perovskite phase SCFM. The excellent oxygen reduction reaction catalytic activity and mixed ionic–electronic conductivity make SCFM an excellent cathode material for SOFCs. When SCFM is used as the anode, excellent performance and stability are achieved upon either direct oxidation of methane as a fuel or operation with sulfur-containing fuels. The excellent redox reversibility coupled with outstanding electrical and catalytic properties manifested by SCFM will enable a broad application in energy conversion applications.

An equivalent circuit has firstly been proposed to evaluate proton-conducting electrolysis cells for their intrinsic electrode performance concealed by electronic conduction in electrolyte.

BackgroundThis study aimed to select piperacillin/tazobactam (TZP) infusion mode guided by Sequential Organ Failure Assessment (SOFA) score in cancer patients with hospital-acquired pneumonia (HAP) postoperation.Patients and methodsA total of 120 cancer patients with postoperative HAP were divided into two groups: improved administration group (L group) and conventional treatment group (Con group). The Con group received traditional infusion of TZP and the L group received it as prolonged infusion. Blood drug concentration was detected at different time points. Based on the SOFA cut-off value of 9, the patients were regrouped into M (mild) and S (severe) groups.ResultsPercent time that the free drug concentrations remain above the minimum inhibitory concentration (%fT>MIC) was longer than 5 h in L group, but <4 h in Con group. Administration method (p=0.033, OX value 2.796, B value 1.028, 95% CI: 0.855–8.934) and SOFA score (p=0.038, OX value 0.080, B value −2.522, 95% CI: 0.007–0.874) were independent predictors of patient survival. In the S group, compared to conventional treatment, prolonged infusion mode resulted in shorter days of antibiotic use and shorter ventilator time, and achieved longer survival, better clinical efficacy, and lower 28-day mortality rate.ConclusionFor cancer patients with SOFA score ≥9, prolonged infusion of TZP could benefit the patients and obtain better clinical efficacy.

Electrocatalysts for the oxygen reduction reaction (ORR) in acidic media are crucial in proton-exchange membrane (PEM) fuel cells and other electrochemical devices. Achieving ideal ORR activity and durability in acidic media remains a challenge. Here, we developed a new NFeCo-CNT/NC nanocomposite electrocatalyst from the highly available and recyclable plant biomass Typha orientalis using a readily scalable approach. The electrocatalyst exhibits excellent ORR activity, superior stability and tolerance to methanol poisoning effects in acidic media. The value of the onset potential and half-peak potential of the typical product is only 70 mV and 65 mV less than that of Pt/C, respectively. The NFeCo-CNT and NFeCo-NC in the nanocomposite have synergistically enhanced ORR activities. The catalyst may have practical applications in fuel cells. One of the important accomplishments of this work is the discovery that trace Fe 3+ and Co 2+ can synergistically catalyze the growth of the carbon nanotubes when melamine serves as the CNT precursor. Fig. 6 (a) The effect of Fe and Co contents on the ORR activity; (b) the effect of annealing temperature on the ORR activity; (c) the effect of annealing time on the ORR activity; (f) the effect of amount of melamine on the ORR activity.This journal is