Of the few weberite-type Na-ion cathodes explored to date, NaFeF exhibits the best performance, with capacities up to 184 mAh/g and energy densities up to 550 Wh/kg reported for this material. However, the development of robust structure-property relationships for this material is complicated by its tendency to form as a mixture of metastable polymorphs, and transform to a lower-energy Na FeF perovskite compound during electrochemical cycling. Our first-principles-guided exploration of Fe-based weberite solid solutions with redox-inactive Mg and Al predicts an enhanced thermodynamic stability of NaMg Fe F as the Mg content is increased, and the = 0.
View Article and Find Full Text PDFAltermagnetism was very recently identified as a new type of magnetic phase beyond the conventional dichotomy of ferromagnetism (FM) and antiferromagnetism (AFM). Its globally compensated magnetization and directional spin polarization promise new properties such as spin-polarized conductivity, spin-transfer torque, anomalous Hall effect, tunneling, and giant magnetoresistance that are highly useful for the next-generation memory devices, magnetic detectors, and energy conversion. Though this area has been historically led by the thin-film community, the identification of altermagnetism ultimately relies on precise magnetic structure determination, which can be most efficiently done in bulk materials.
View Article and Find Full Text PDFBackground: Full coverage of childhood vaccines is a persistent challenge in low- and middle-income countries, suggesting the presence of specific contextual barriers. The emergence of the COVID-19 pandemic further worsened the situation. The complementary use of community-based participatory research (CBPR) and human-centered design (HCD) approaches has the potential to effectively create tailored interventions for improving public health outcomes.
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