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Liquid metals typically do not intrinsically wet oxide surfaces due to chemical dissimilarity, preventing the formation of well-bonded interfaces in many applications. This paper investigates how the wetting and spreading of liquid silver (Ag) droplets on oxide surfaces can be enhanced via patterned nickel (Ni) particles using multiscale modeling. First, a force field (FF) for an Ag/yttria-stabilized-zirconia system was developed by fitting the interfacial binding energy to density-functional theory (DFT) calculations. Then, molecular dynamics (MD) simulations using these FF parameters revealed that the good wetting of Ag on Ni caused Ag droplets to be attracted to the Ni particles, promoting spreading. Thus, the optimal hexagonal Ni pattern was shown to enhance the wetting area by 224% compared to a bare oxide surface. Second, an analytical model predicting the maximum possible enhancement in wetting area as a function of the intrinsic wetting angle, size of the Ag droplet, and size of the Ni particles was derived and validated with MD simulations, to generalize this method to other substrates. Both the analytical model and MD results suggested that the ability of Ni patterns to enhance the Ag wetting area becomes more significant as the wettability of substrate becomes worse. [ABSTRACT FROM AUTHOR]

Sr surface segregation in mixed-cation oxides often causes degradation of chemical or electrochemical performance. In this work, the thermodynamic driving force for Sr segregation is investigated to explain the Sr segregation behavior in La 0.5 Sr 0.5 FeO 3 (LSF). Specifically, Density Functional Theory is used to calculate the surface Gibbs free energy of various surface terminations of cubic (100) LSF as a function of chemical potential and temperature. SrO-terminated surfaces are predicted to be dominant, promoting Sr segregation at high temperatures and low oxygen partial pressure. [Display omitted] • Thermodynamic driving force for Sr segregation was computationally determined. • SrO termination becomes thermodynamically more favorable as temperature increases. • DFT + thermodynamics model agrees with experimental observation. [ABSTRACT FROM AUTHOR]

Intermittent electricity generation and stationary grid storage are increasingly competitive with ongoing efforts to advance technologies towards market diffusion. We contribute an innovation systems perspective to understand better the co-evolution of early-stage public investments in research, development and demonstration, costs, and diffusion of technology and policy for intermittent renewables and storage in two federalist political systems (Canada and the United States). Our systematic review comparatively examines public investments in wind, solar, and storage technologies, as well as trends in costs, policy, and technology diffusion up to and including 2019. Our review contributes an account of the diffusion of renewable portfolio standards (RPS) as well as storage policies and targets at the subnational level in both countries. We quantify progress to policy goals, with findings pointing to substantial variability in the contribution of intermittent generation. Five states and one province surpassed goals with wind and solar power alone. One state and one province had less than 2% contribution from intermittent generation. While wind has a dominant force in meeting RPS goals in the United States, credit multipliers and carve-outs recently have resulted in high growth in solar power. Deployment of stationary storage is relatively nascent compared to wind and solar power, with increasing technology and policy diffusion very recently spurred by cost decreases in battery options. We identify data gaps that can be filled with more robust tracking of innovation metrics such as costs of storage technologies. Findings offer insight into how the interplay between costs, deployment, and policies can support improvements in energy technology innovation systems. • A new application of systematic review to clean energy innovation. • Wind power is the dominant intermittent contributor to renewable standards. • Policy diffusion for intermittent power is more advanced than grid storage. • Better reporting systems of costs will enable more robust comparisons. [ABSTRACT FROM AUTHOR]

In the present study, a novel mutation in exon 7 of presenilin 1 (Leu232Pro) was discovered in a Korean patient with early-onset Alzheimer's disease, who represented memory decline at 37 years of age, followed by impairment in spatial activity and concentrations and personality changes. Imaging analyses with magnetic resonance scan showed diffuse atrophy in the frontoparietal regions. Targeted next generation sequencing and Sanger sequencing identified a heterozygous T to C transition at position 695 (c.695T>C) of in presenilin 1 gene ( PSEN1 ), resulting in a novel missense mutation at codon 232 from leucine to proline (L232P). Several family members of the patient developed dementia, suggesting an autosomal dominant inheritance; however, we were unable to perform a segregation analysis to confirm this. Since the proline may play a role as a helix breaker, this mutation could significantly disturb the transmembrane helix domain-V of PSEN1 and perturb its protein functions. This hypothesis was supported by the results from the in silico analyses, predicted a major kink on this helix. Several leucine>proline substitutions in other PSEN1 transmembrane helices revealed aggressive AD phenotypes. Future functional studies would be needed to evaluate the pathogenicity of this mutation in AD. [ABSTRACT FROM AUTHOR]

[Display omitted] • DFT-informed theory predicts inner potential maps in solid-state batteries. • Potential drops lead to "intrinsic" interfacial impedance. • Computed dictionary of potential maps for 48 distinct solid-state batteries. • Identified cathode/solid-electrolyte interfaces with low intrinsic impedance. • Model bridges materials innovation with device performance. All-solid-state batteries are an exciting technology for increased safety and energy density compared to traditional lithium-ion cells. Recently, we developed a theory of mapping inner potentials and thermodynamic driving forces specific to the solid-state batteries, allowing prediction of the "intrinsic" interfacial lithium barriers. This potential mapping methodology, based purely on calculated bulk and surface properties, enables fast screening of a variety of advanced solid electrolyte materials as well as a selection of cutting-edge high-voltage cathode materials, predicting properties of 48 distinct battery configurations. A number of cathode/electrolyte pairs are identified which have low "intrinsic" barriers to both the charge and discharge process at all states of charge, suggesting that they will most benefit from engineering efforts to reduce extrinsic interfacial impedance. These predictions agree well with available experimental measurements, which form only a subset of the predicted interfaces. Thus, this interface potential model will accelerate the design process from emerging materials to all-solid-state battery devices. [ABSTRACT FROM AUTHOR]

The metal current collectors used in electronic, energy conversion, and energy storage devices often have difficulty wetting and adhering to ceramic substrates. Here, a novel Particle Interlayer Directed Wetting and Spreading (PIDWAS) technique is demonstrated that utilizes 1) the low wetting angle of silver on nickel and 2) the high work of adhesion between nickel and various ceramics to produce well-adhered, self-assembled silver patterns on ceramics not normally wet by silver. This is achieved by partially sintering nickel patterns and melt infiltrating either 1) locally-applied silver or 2) silver that simultaneously dewets the bare ceramic and laterally spreads through the porous nickel network. The resulting Ag-Ni patterns have higher ceramic adhesion strengths, higher densities, and similar electronic resistivities to those made using commercially-available silver circuit pastes. Further, these dense Ag-Ni patterns can be produced without externally-applied pressure, making them desirable for circuit, sealing, die-attach, joining and other applications. Image, graphical abstract [ABSTRACT FROM AUTHOR]