The proton conduction mechanism for the ceramic proton conductor BaZr_0.7Ce_0.2Y_0.1O_3−δ was observed by quasi-elastic neutron spectroscopy and described in detail.

Plasma-treated water (PTW) recently entered science as a sanitizing agent, which possess the capability for on-demand production. It offers interesting possibilities for sustainable and resource-saving applications in healthcare and food production. The present study monitors the impact of PTW on suspended cells before the biofilm formation of the putrefactive bacterium B. subtilis. Light and electron microscope imaging captures the maturing of growing biofilms within the first 24 h. Microbiological assays (proliferation, LIVE/DEAD, and XTT), which mirror the proliferation of the bacterium, the metabolic activity, and the integrity of the cell membrane, underpinning the metabolic response of still-suspended cells. B. subtilis cells without any treatment build up a resistive biofilm within the 24 h. Cells that remain in the supernatant predominantly appear as monomers or dimers. Treated B. subtilis cells have hampered biofilm formation and were not able to build up a confluent growing biofilm within the first 24 h. Moreover, the microscopic observation of PTW-treated suspension showed cellular aggregates with an unusually high connectivity of the individual cells. The findings suggest this cellular reaction as a counter measure against the adverse impact of PTW treatment. The experiments show the adverse impact of PTW on B. subtilis–biofilm formation and the phenomenological reaction of B. subtilis.

Mixed ionic electronic conductor (MIEC) membranes provide a great route for introducing oxygen to combustion and reforming processes of new fuels such as green ammonia. Ba_0.5Sr_0.5Co_0.8Fe_0.2O_{3- δ} (BSCF) is known to be one of the most widely utilized perovskite material applied as oxygen transport membrane, as it possesses elevated oxygen permeability up to 7 ml(STP)·min^-1·cm^-2 at a temperature range of 850-900°C. Application of thin MIEC films of thicknesses of around 500 nm – 5 µm allow for reduction of Ohmic resistance for transport processes and sufficient oxygen permeation at lower temperatures as compared to bulk membranes, which is of great advantage with regard to materials stability and quality of sealing. However, fabrication techniques of thin MIEC membranes staunchly influence their phase purity. Crystallinity, microstructure and correlated oxygen diffusion properties as well as stability of membrane-substrate interfaces. Physical vapour deposition (PVD) such as magnetron sputtering (MS) is successfully applied to produce a dense and pinhole-free membrane with thicknesses ranging from 100 nm nanometer to a few micrometers. Challenges due to large size porosity of the ceramic substrate were addressed by tuning of the substrate porosity, ensuring formation of a continues layer and stability of the thin membranes. In this work, we report on the influence of the MS process parameters, as well as subsequent annealing techniques of both thermal annealing (TA) and line beam Laser annealing (LA) on the microstructure of a fabricated asymmetric membrane (AsM) consisting of BSCF thin membrane on a BSCF support wit tunable pore sizes. Oxygen permeability of the AsM was investigated at high temperatures (850-900 °C). For a substrate pore size of around 3 µm, BSCF membrane thicknesses of 1 to 5 µm could be applied for fabrication of AsM, resulting in a 2-fold increase of oxygen permeability ~5 ml.min^-1.cm^-2 at a temperature of 900 °C as compared to a bulk BSCF support of ~2 mm thickness, whereas comparable oxygen permeation is already reached at a temperature of 700°C by the thin membrane. Contrariwise, the one with high porosity (~10 µm) required the deposition of thicker layers, which obstruct the oxygen diffusion and inhibited the permeation. The results have optimised sputtering process parameters, supports porosity and TA&/SLA parameters, are key factors for producing thin film membrane exhibiting high oxygen flux and good stability.

Ammonia is the of the most crucial chemicals and currently primarily produced through the Haber-Bosch process causing the industrial ammonia production to emit more CO₂ than any other chemical-making reaction. While the current primary function of ammonia lies within the fertilizer production, it can also be directly used as a fuel for power generation or in the maritime industry. Compared to hydrogen, ammonia has superior storage and transportation capabilities due to its greater volumetric energy density and mild conditions for liquefication. Given the need of reducing global carbon emissions, ammonia could be synthesized electrochemically using air, water and electricity by the Solid-State Ammonia Synthesis (SSAS). Protonic ceramic cells operate within an intermediate temperature regime of around 450 - 550 °C which is well suited for this process. Within our work, we present a tubular membrane electrode unit entirely made of ceramic components based on a barium zirconate thin film electrolyte. An ammonia production rate of 9.06 × 10^-10 mol s^-1 cm^-2 and a Faradaicefficiency of 6.58% were achieved using a NiO-BaZr_0.7Ce_0.2Y_0.1O_{3- δ} | BaZr_0.8Y_0.2O_{3- δ} | Ru@Ba_0.5Sr_0.5TiO_3-δ cell. A key innovation lies in the production of dense BaZr0.8Y0.2O3-δ electrolyte layers, ranging from 1 to 5 µm in thickness, utilizing a Closed-Field Unbalanced Magnetron Sputtering (CFUMS) process. This technique allows precise adjustments of stoichiometric ratios within the perovskite structure, offering improved sputtering yields compared to conventional methods. Furthermore, the crystallinity, phase purity, and microstructure of sputter-deposited thin films are enhanced through selective laser annealing (SLA), resulting in high-density films composed of single-phase BaZr0.8Y0.2O3-δ with average crystallite sizes of 200 nm while avoiding substrate damage from thermal stress. Electrochemical performance was evaluated through impedance spectroscopy, half-cell tests and full cell tests providing insights into the efficacy of the developed tubular membrane reactor for the electrochemical synthesis of ammonia. The results demonstrate the feasibility of utilizing ceramic proton conductors in SSAS, particularly highlighting the potential of high-pressure operation up to 80 bars in tubular cells at relatively low temperatures around 450 °C, thereby achieving attractive NH₃ production rates. This research contributes to the evolving landscape of sustainable ammonia synthesis by presenting a novel approach that integrates advanced materials and manufacturing techniques. Electrification and decentralization of the ammonia supply chain will expand the market by supporting its current use as fertilizer source and enable a new route as green energy carrier paving the way for an ammonia-based economy. Figure 1