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Polycrystalline ion conductors are widely used as solid electrolytes in energy storage technologies. However, they often exhibit poor ion transport across grain boundaries and pores. This work demonstrates that strategically tuning the mesoscale microstructures, including pore size, pore distribution, and chemical compositions of grain boundaries, can improve ion transport. Using LiTa₂PO₈as a case study, we have shown that the combination of LiF as a sintering agent with Hf⁴⁺implantation improves grain-grain contact, resulting in smaller, evenly distributed pores, reduced chemical contrast, and minimized nonconductive impurities. A suite of techniques has been used to decouple the effects of LiF and Hf⁴⁺. Specifically, LiF modifies particle shape and breaks large pores into smaller ones, while Hf⁴⁺addresses the chemical mismatches between grains and grain boundaries. Consequently, this approach achieves nearly two orders of magnitude improvement in ion conduction. Tuning mesoscale structures offers a cost-effective method for enhancing ion transport in polycrystalline systems and has notable implications for synthesizing high-performance ionic materials. 

The Cl–S mixed-anion sublattice of Li_1.6AlCl_3.4S_0.6creates face- and edge-shared octahedra that connect to form 3D ion conduction pathways with low activation energy barriers. 

Antibodies are proteins that can protect against disease using a variety of mechanisms, including binding to pathogens and targeting them for destruction. Structural modeling of antibody binding to the SARS-Cov-2 spike protein and how mutations might allow viruses to escape antibody neutralization has been previously investigated in Antibody Engineering Hackathons. The procedure for investigating immune escape can be used for students in affordable and accessible Course-Based Undergraduate Research Experiences (CUREs). In this work, we adapted and expanded the SARS-Cov-2 protocol to address new pathogens, including hookworms, Respiratory Syncytial Virus (RSV), Influenza, and Enterovirus D68. We found each presented unique challenges; however, these challenges present opportunities for student research. We describe how modifications to the SARS-Cov-2 protocol designed for SARS-CoV-2 could allow students to investigate the impact of mutations in each of these pathogens when binding to antibodies. 

Li_3.6In₇S_11.8Cl has a face-centered cubic arrangement of S²⁻/Cl⁻stabilized by Li⁺/In³⁺that form 3D ion conduction paths. The moisture stability and fast ion conduction make Li_3.6In₇S_11.8Cl a promising electrolyte for solid-state batteries. 

Abstract All‐solid‐state potassium batteries emerge as promising alternatives to lithium batteries, leveraging their high natural abundance and cost‐effectiveness. Developing potassium solid electrolytes (SEs) with high room‐temperature ionic conductivity is critical for realizing efficient potassium batteries. In this study, we present the synthesis of K_2.98Sb_0.91S_3.53Cl_0.47, showcasing a room‐temperature ionic conductivity of 0.32 mS/cm and a low activation energy of 0.26 eV. This represents an increase of over two orders of magnitude compared to the parent compound K₃SbS₄, marking the highest reported ionic conductivity for non‐oxide potassium SEs. Solid‐state³⁹K magic‐angle‐spinning nuclear magnetic resonance on K_2.98Sb_0.91S_3.53Cl_0.47reveals an increased population of mobile K⁺ions with fast dynamics. Ab initio molecular dynamics (AIMD) simulations further confirm a delocalized K⁺density and significantly enhanced K⁺diffusion. This work demonstrates diversification of the anion sublattice as an effective approach to enhance ion transport and highlights K_2.98Sb_0.91S_3.53Cl_0.47as a promising SE for all‐solid‐state potassium batteries. 

Mantle-derived, low-degree melts, such as kimberlites, carbonate-rich olivine lamproites (CROLS), and cratonic olivine lamproites, are the main carriers of diamonds. They are rare ultramafic, volatile-rich volcanic magmas, generally restricted to stable cratons, and are the deepest-sourced magmas erupted onto Earth’s surface. As hybrid magmas, their formation mechanism and mantle sources remain enigmatic and highly debated, especially the nature of the processes leading to their “enriched” isotopic signatures. The often extreme isotopic compositions of Sr, Nd, Pb, and Hf suggest that the mantle sources of these magmas vary between an ancient and geochemically depleted component and various enriched components. The enriched components could include crustal material recycled into the convective mantle or metasomatized lithospheric mantle. For the latter, discriminating between assimilation by sub-lithospheric magmas during the ascent or melting of element-enriched material from within the lithospheric mantle is paramount concerning petrogenesis. As the stable isotope composition of K, and Ba vary between surface and mantle reservoirs, they are well-suited tools for addressing the cause of different radiogenic isotopic signatures and to better constrain the mantle sources of these important magmas. Here, we use collision cell multi-collector inductively-coupled-plasma mass-spectrometry (MC-ICP-MS) and traditional MC-ICP-MS to conduct the first comprehensive whole-rock K and Ba stable isotope study on a wide range of low-degree mantle-derived melts. All the deep-seated, low-degree melts analyzed here show no correlation between melting/differentiation indices and δ41K and δ138Ba compositions, implying that any isotopic fractionation during melting or eruption was limited and that the different mantle and crustal reservoirs affecting these melts dominate their isotopic variability. Overall, kimberlites show limited δ41K and δ138Ba variability, with a median δ41K of -0.40 ± 0.06‰ (2SE) and δ138Ba of 0.00 ± 0.07‰ (2SE), within error relative to an estimated bulk silicate Earth [(BSE: δ41K= -0.42±0.07‰ (2SD) and δ138Ba=0.03±0.04‰ (2SD)], suggesting significant sublithospheric input. While the sample size is small (N=4), Canadian kimberlites from Lake De Gras display a bi-modal distribution with δ41K values slightly higher and lower relative to BSE, ascribed to crustal and lithospheric contamination. Like kimberlites, South African CROLS show limited K isotope variability with a median δ41K of -0.48 ± 0.02‰ (2SE). Their compositions are non-resolvable from two Mica-Amphibole-Rutile-Ilmenite-Diopside (MARID) xenoliths. The δ138Ba of the CROLS also shows limited variation with a median δ138Ba of 0.00 ± 0.07‰ (2SE), plotting within BSE estimations. Compared to the other low-degree mantle-derived melts, cratonic olivine/leucite-bearing lamproites from West Australia show a wide range in δ41K (-0.97‰ to +0.34‰) and δ138Ba (-0.30‰ to +0.27) values. The observed large K isotopic variation in cratonic lamproites is similar to that observed in post-collisional lamproites and is ascribed to sediment recycling. Argyle lamproites define robust correlations between potassium and barium elemental abundances, and their stable isotopes call for significant hydrothermal fluid-assisted leaching and isotopic fractionation.