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Expone el autor las cuestiones hermenéuticas y metodológicas que afrontó a la hora de redactar el proyecto de declaración hacia una ética mundial. Éste, tras un largo proceso que aquí se resume, fue suscrito por numerosos y destacados representantes religiosos. La determinación de una exigencia ética primordial: «Todo hombre debe ser tratado humanamente» y la presencia de la regla de oro en todas las confesiones hacen posible este consenso ético de perentoria necesidad para el mundo y proclamado públicamente por primera vez en la Historia de las religiones.

Aerosol deposition (AD) method is a kind of additive manufacturing technology for fabricating dense films such as metals and ceramics at room temperature. It resolves the challenge of integrating ceramic films onto temperature-sensitive substrates, including metals, glasses, and polymers. It should be emphasized that the AD is a spray coating technology that uses powder without thermal assistance to generate films with high density. Compared to the traditional sputter-based approach, the AD shows several advantages in efficiency, convenience, better interfacial bonding and so on. Therefore, it opens some possibilities to the field of batteries, especially all-solid-state batteries (ASSBs) and draws much attention not only for research but also for large scale applications.The purpose of this work is to provide a critical review on the science and technology of AD as well as its applications in the field of batteries. The process, mechanism and effective parameters of AD, and recent developments in AD applications in the field of batteries will be systematically reviewed so that a trend for AD will be finally provided.

Summary: A robust imaging protocol utilizing laboratory XCT is presented. Hybrid 2D/3D imaging at different scales with real-time monitoring allowed to assess, in operation, the evolution of zinc electrodes within three environments, namely alkaline, near-neutral, and mildly acidic. Different combinations of currents were used to demonstrate various scenarios exhibiting both dendritic and smooth deposition of active material. Directly from radiograms, the volume of the electrode and therefore its growth/dissolution rate was estimated and compared against tomographic reconstructions and theoretical values. The protocol combines simplistic cell design with multiple three-dimensional and two-dimensional acquisitions at different magnifications, providing a unique insight into electrode’s morphology evolution within various environments.

Abstract Supporting electrolytes contain inert dissolved salts to increase the conductivity, to change microenvironments near the electrodes and to assist in electrochemical reactions. This combined experimental and computational study examines the impact of supporting salts on the ion transport and related limited currents in electrochemical cells. A physical model that describes the multi-ion transport in liquid electrolytes and the resulting concentration gradients is presented. This model and its parameterization are evaluated by the measured limited current of the copper deposition in a CuSO4 electrolyte under a gradually increasing amount of Na2SO4 that acts as a supporting salt. A computational sensibility analysis of the transport model reveals that the shared conductance between the ions lowers the limited currents with larger supporting salt concentrations. When the supporting salt supplies most of the conductance, the electric-field-driven transport of the electrochemically active ions becomes negligible so that the limited current drops to the diffusion-limited current that is described by Fick’s first law. The transition from diluted supporting electrolyte to the case of ionic liquids is elucidated with the transport model, highlighting the different physical transport mechanisms in a non-conducting (polar) and a conducting (ionic) solvent.

Abstract Pseudocapacitances such as the hydrogen adsorption on platinum (HAoPt) are associated with faradaic chemical processes that appear as capacitive in their potentiodynamic response, which was reported to result from the kinetics of adsorption processes. This study discusses an alternative interpretation of the partly capacitive response of the HAoPt that is based on the proton transport of ad- or desorbed hydrogen in the double layer. Potentiodynamic perturbations of equilibrated surface states of the HAoPt lead to typical double layer responses with the characteristic resistive–capacitive relaxations that overshadow the fast adsorption kinetics. A potential-dependent double layer representation by a dynamic transmission line model incorporates the HAoPt in terms of capacitive contributions and can computationally reconstruct the charge exchanged in full range cyclic voltammetry data. The coupling of charge transfer with double layer dynamics displays a novel physicochemical theory to explain the phenomenon of pseudocapacitance and the mechanisms in thereon based supercapacitors.

Abstract A direct current in an electrochemical cell with a diluted liquid electrolyte leads to the displacement of ions within the solvent, while diffusion works against the resulting concentration differences. This study aims to experimentally evaluate a physicochemical ion transport model (source code provided) that describes current‐driven concentration gradients in diluted electrolytes. Hereto, an aqueous 0.1 M CuSO4 electrolyte between metallic copper electrodes serves as an experimental test system. Spatially resolved optical measurements are used to monitor the evolution of the ion concentration gradient in the electrolyte. Moreover, measured limited currents are related to computationally modeled concentration gradients. A constant parameterization of the diffusion coefficient, molar conductivity and ion transport number lead to a slight overestimation of the cathodic ion depletion and cell resistance, whereas a literature data based concentration dependent parameterization matches better to the measured data. The limited current is considered under a computational parameter variation and thereby related to the physicochemical impact of different electrolyte properties on the ion transport. This approach highlights the differences between purely diffusion limited currents and the limited current resulting from the combined electric field and diffusion driven ion motion. A qualitative schematic sketch of the physical mechanisms of the ion movement is presented to illustrate the current driven ion displacement in liquid electrolytes.

Abstract Efficiently improving the moisture stability of β‐Li3PS4 materials could significantly reduce production costs and eventually enable the mass application. Nanoporous multiphase β‐Li3PS4 materials prepared via solvent‐assistant routes usually contain solvent or solvent decomposition segments associated with the amorphous Li3PS4 phase in their structures. Herein, the solvent ethyl propionate (EP) remains in the β‐Li3PS4 even after 220 h of annealing at 220°C. The possibility of tuning the moisture stability of β‐Li3PS4 by adjusting the content of the solvent is investigated by environmental scanning electron microscopy (ESEM) combined with other structural analysis techniques. The results demonstrated that the hydrogen‐containing amorphous Li3PS4 not only stabilizes the β‐phase at room temperature but also improves the moisture stability of the material. Although the rapid hydrolysis occurs on the surface of solvent‐containing β‐Li3PS4 materials under ambient conditions within 10 s, with 4 wt% EP content, the material can be exposed to 1.6% relative humidity (R.H.) for at least 8 h without any structural or microstructural change. Even with the lower amount of EP (1.2 wt%) in the Li3PS4 structure, the material can withstand 1% R.H. for more than 8 h, which allows the material to be manufactured in a dry room. Our observation proposes a simple method to slightly modify the moisture stability of β‐Li3PS4 to match the different manufacturing conditions.

An innovative approach for the design of air electrodes for metal–air batteries are free-standing scaffolds made of electrospun polyacrylonitrile fibres. In this study, cobalt-decorated fibres are prepared, and the influence of carbonisation temperature on the resulting particle decoration, as well as on fibre structure and morphology is discussed. Scanning electron microscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, elemental analysis, and inductively coupled plasma optical emission spectrometry are used for characterisation. The modified fibre system is compared to a benchmark system without cobalt additives. Cobalt is known to catalyse the formation of graphite in carbonaceous materials at elevated temperatures. As a result of cobalt migration in the material the resulting overall morphology is that of turbostratic carbon. Nitrogen removal and nitrogen-type distribution are enhanced by the cobalt additives. At lower carbonisation temperatures cobalt is distributed over the surface of the fibres, whereas at high carbonisation temperatures it forms particles with diameters up to 300 nm. Free-standing, current-collector-free electrodes assembled from carbonised cobalt-decorated fibre mats display promising performance for the oxygen reduction reaction in aqueous alkaline media. High current densities at an overpotential of 100 mV and low overpotentials at current densities of 333 μA·cm−2 were found for all electrodes made from cobalt-decorated fibre mats carbonised at temperatures between 800 and 1000 °C.

Abstract Lithium aluminum titanium phosphate (LATP) is one of the materials under consideration as an electrolyte in future all-solid-state lithium-ion batteries. In ceramic processing, the presence of secondary phases and porosity play an important role. In a presence of more than one secondary phase and pores, image analysis must tackle the difficulties about distinguishing between these microstructural features. In this study, we study the phase evolution of LATP ceramics sintered at temperatures between 950 and 1100 °C by image segmentation based on energy-dispersive X-ray spectroscopy (EDS) elemental maps combined with quantitative analysis of LATP grains. We found aluminum phosphate (AlPO4) and another phosphate phase ((Lix)PyOz). The amount of these phases changes with sintering temperature. First, since the grains act as an aluminum source for AlPO4 formation, the aluminum content in the LATP grains decreases. Second, the amount of secondary phase changes from more (Lix)PyOz at 950 °C to mainly AlPO4 at 1100 °C sintering temperature. We also used scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) to study the evolution of the LATP grains and AlPO4, and LATP grain size increases with sintering temperature. In addition, transmission electron microscopy (TEM) was used for the determination of grain boundary width and to identify the amorphous structure of AlPO4.

Abstract Hybrid electrolytes are developed to meet the requirements of safety, performance, and manufacturing for electrolytes suitable for Li‐ion batteries with Li‐anodes. Recent challenges—in addition to these key properties—emphasize the importance of sustainability. While compromising between these three objectives, the currently available materials are still well below the targeted goals. Three important issues for the design of hybrid electrolytes are (i) the role of the morphology and surface state of the ceramic particles in the polymer matrix, (ii) the dependence of salt concentration and ionic conductivity and, (iii) the effects of substituting part of the polyethylene oxide (PEO), with biopolymers. Electrolyte films were prepared from PEO, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), Li6.5La3Zr1.5Ta0.5O12 (LLZO:Ta), and biopolymers with varying contents of these components by a solution casting method. The films were analyzed with respect to structural and microstructural characteristics by DSC, Raman spectroscopy, and SEM. Ionic conductivity was evaluated by electrochemical impedance spectroscopy. Most interesting, when comparing films with LLZO:Ta versus without, the content of LiTFSI required for the maximum conductivity in the respective systems is different: a higher LiTFSI concentration is required for the former type. Overall, addition of LLZO:Ta as well as partial substitution of PEO by chitosan mesylate or cellulose acetate decrease the ionic conductivity. Thus—at least in the present approaches—a loss in performance is the drawback from attempts to enhance the safety by LLZO:Ta additions and sustainability by biopolymer blending of hybrid electrolytes.