Data sharing practices and data availability upon request differ across scientific disciplines.

Data sharing is one of the cornerstones of modern science that enables large-scale analyses and reproducibility. We evaluated data availability in research articles across nine disciplines in Nature and Science magazines and recorded corresponding authors' concerns, requests and reasons for declining data sharing. Although data sharing has improved in the last decade and particularly in recent years, data availability and willingness to share data still differ greatly among disciplines. We observed that statements of data availability upon (reasonable) request are inefficient and should not be allowed by journals. To improve data sharing at the time of manuscript acceptance, researchers should be better motivated to release their data with real benefits such as recognition, or bonus points in grant and job applications. We recommend that data management costs should be covered by funding agencies; publicly available research data ought to be included in the evaluation of applications; and surveillance of data sharing should be enforced by both academic publishers and funders. These cross-discipline survey data are available from the plutoF repository.

Spin-coated [Formula: see text] solar cells: A study on the transformation from ink to film.

In this paper, we study the DMSO/thiourea/chloride salt system for synthesis of pure-sulfide [Formula: see text] (CZTS) thin-film solar cells under ambient conditions. We map out the ink constituents and determine the effect of mixing time and filtering. The thermal behavior of the ink is analyzed, and we find that more than 90% of the solvent has evaporated at [Formula: see text]. However, chloride and sulfoxide species are released continually until [Formula: see text], suggesting the advantage of a higher pre-annealing temperature, which is also commonly observed in the spin-coating routines in literature. Another advantage of a higher pre-annealing temperature is that the worm-like pattern in the spin-coated film can be avoided. We hypothesize that this pattern forms as a result of hydrodynamics within the film as it dries, and it causes micro-inhomogeneities in film morphology. Devices were completed in order to finally evaluate the effect of varying thermal exposure during pre-annealing. Contrary to the previous observations, a lower pre-annealing temperature of [Formula: see text] results in the best device efficiency of 4.65%, which to the best of our knowledge is the highest efficiency obtained for a pure-sulfide kesterite made with DMSO. Lower thermal exposure during pre-annealing results in larger grains and a thicker [Formula: see text] layer at the CZTS/Mo interface. Devices completed at higher pre-annealing temperatures display the existence of either a Cu-S secondary phase or an incomplete sulfurization with smaller grains and a fine-grain layer at the back interface.

Passivation and activation of La0.6Sr0.4FeO3 thin film electrodes.

The oxygen exchange activity of thin dense La0.6Sr0.4FeO3 electrodes prepared by pulsed laser deposition was investigated by electrochemical impedance spectroscopy and electrical conductivity relaxation below 600 °C. The value of the surface exchange coefficient (kchem) measured at 491 °C decreased from an initial 4.4 × 10-6 cm s-1 to 1.7 × 10-7 cm s-1 after aging for 7 days. The rapid decrease in the oxygen exchange rate was accompanied by the increase in the surface concentration of 'non-lattice strontium' detected by X-ray photoelectron spectroscopy. Subsequent electrochemical tests over 40 days showed that the electrode performance could be recovered by rinsing the passivated electrode in deionized water. Repeated treatments eventually also led to improved stability of electrochemical performance.

Direct in situ probe of electrochemical processes in operating fuel cells.

The function of systems and devices in many technologically important applications depends on dynamic processes in complex environments not accessible by structure and property characterization tools. Fuel cells represent an example in which interactions occur under extreme conditions: high pressure, high temperature, in reactive gas environments. Here, scanning surface potential microscopy is used to quantify local potential at electrode/electrolyte interfaces in operating solid oxide fuel cells at 600 °C. Two types of fuel cells are compared to demonstrate two mechanisms of ionic transport at interfaces. Lanthanum strontium ferrite-yttria-stabilized zirconia (LSF-YSZ) and lanthanum strontium manganite-yttria-stabilized zirconia (LSM-YSZ) cross-sectional electrode assemblies were measured to compare mixed ionic electronic conducting and electronic conducting mechanisms. Direct observation of the active zones in these devices yields characteristic length scales and estimates of activation barrier changes.