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We demonstrate enhanced Li+ transport through the selectively solvated ionic layers of a single-ion conducting polymer. The polymer is a precisely segmented ion-containing multiblock copolymers with well-defined Li+SO3– ionic layers between crystallized linear aliphatic 18-carbon blocks. X-ray scattering reveals that the dimethyl sulfoxide (DMSO) molecules selectively solvate the ionic layers without disrupting the crystallization of the polymer backbone. The amount of DMSO (∼21 wt %) calculated from the increased layer spacing is consistent with thermogravimetric analysis. The ionic conductivity through DMSO-solvated ionic layers is >104 times higher than in the dried state, indicating a significant enhancement of ion transport in the presence of this solvent. Dielectric relaxation spectroscopy (DRS) further elucidates the role of the structural relaxation time (τ) and the number of free Li+ (n) on the ionic conductivity (σ). Specifically, DRS reveals that the solvation of ionic domains with DMSO contributes to both accelerating the structural relaxation and the dissociation of ion pairs. This study is the initial demonstration that selective solvation is a viable design strategy to improve ionic conductivity in nanophase separated, single-ion conducting multiblock copolymers. 

We investigate a new series of precise ion-containing polyamide sulfonates (PAS x Li), where a short polar block precisely alternates with a non-polar block of aliphatic carbons ( x = 4, 5, 10, or 16) to form an alternating (AB) n multiblock architecture. The polar block includes a lithiated phenyl sulfonate in the polymer backbone. These PAS x Li polymers were synthesized via polycondensation of diaminobenzenesulfonic acid and alkyl diacids (or alkyl diacyl chlorides) with x -carbons, containing amide bonds at the block linkages. The para - and meta -substituted diaminobenzene monomers led to polymer analogs denoted p PAS x Li and m PAS x Li, respectively. When x ≤ 10, the para -substituted diamine monomer yields multiblock copolymers of a higher degree of polymerization than the meta -substituted isomer, due to the greater electron-withdrawing effect of the meta -substituted monomer. The PAS x Li polymers exhibit excellent thermal stability with less than 5% mass loss at 300 °C and the glass transition temperatures ( T g ) decrease with increasing hydrocarbon block length ( x ). Using the random phase approximation, the Flory–Huggins interaction parameter ( χ ) is determined for p PAS10Li, and χ (260 °C) ∼ 2.92 reveals high incompatibility between the polar ionic and non-polar hydrocarbon blocks. The polymer with the longest hydrocarbon block, p PAS16Li, is semicrystalline and forms well-defined nanoscale layers with a spacing of ∼2.7 nm. Relative to previously studied polyester multiblock copolymers, the amide groups and aromatic rings permit the nanoscale layers to persist up to 250 °C and thus increase the stability range for ordered morphologies in precise ion-containing multiblock copolymers. 

We describe our year-long astronomy program to engage middle and high school students with visual impairments (VI). The program bridges STEM skills acquired in school with out-of-school experiences to build student capacity for recognizing and pursuing STEM-related higher education and careers. The program combines mentorship experiences with a Project-Based Learning (PBL) curriculum that focuses on NGSS science and engineering practices and content. The paper begins with a description of unique 3D tactile models developed for the program. We then briefly describe recruitment and demographics of participating students with VI. The main part of the paper describes the 12-month PBL curriculum and connections with NGSS science and engineering practices and content focus areas. The full curriculum and implementation time line are provided in the supplemental material. External and internal evaluations of the program are described. Internally we evaluate the performance of our participating students in the areas of retention, communication, energy/enthusiasm, and responses to curriculum prompts. A rubric is developed to evaluate submitted assignments. Scores are provided and discussed from both a scientist evaluator and teacher evaluators. We conclude with a discussion and summary of crucial elements that contributed to increased retention/engagement, improved communication, and prolonged enthusiasm in STEM activities. 

Solid‐state lithium (Li) metal batteries (LMBs) have been developed as a promising replacement for conventional Li‐ion batteries due to their potential for higher energy. However, the current solid‐state electrolytes used in LMBs have limitations regarding mechanical and electrochemical properties and interfacial stability. Here, a fluorine (F)‐containing solid polymer electrolyte (SPE) having a bi‐continuous structure of F‐containing elastomers and plastic crystals is reported. The trifluoroethyl acrylate‐based SPE (T‐SPE) exhibits high ionic conductivity over 10⁻³ S cm⁻¹, superior mechanical elasticity, and robust LiF‐rich interphases at both the Li metal anode and the LiNi_0.83Mn_0.06Co_0.11O₂cathode. Full cells with thin T‐SPEs and low negative/positive capacity ratios below 0.5 at the high‐operating voltage of 4.5 V demonstrate a high specific energy of 538 Wh kg_{anode+cathode+electrolyte}⁻¹and maintain 393 Wh kg⁻¹at a high specific power of 804 W kg_{anode+cathode+electrolyte}⁻¹. The F‐containing phase‐separated SPE system provides a powerful strategy for achieving high‐energy and ‐power solid‐state LMBs.