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Abstract Sodium–oxygen (Na–O₂) batteries are considered a promising energy storage alternative to current state‐of‐the‐art technologies owing to their high theoretical energy density, along with the natural abundance and low price of Na metal. The chemistry of these batteries depends on sodium superoxide (NaO₂) or peroxide (Na₂O₂) being formed/decomposed. Most Na–O₂batteries form NaO₂, but reversibility is usually quite limited due to side reactions at interfaces. By using new materials, including a highly active catalyst based on vanadium phosphide (VP) nanoparticles, an ether/ionic liquid‐based electrolyte, and an effective sodium bromide (NaBr) anode protection layer, the sources of interface reactivity can be reduced to achieve a Na–O₂battery cell that is rechargeable for 1070 cycles with a high energy efficiency of more than 83%. Density functional theory calculations, along with experimental characterization confirm the three factors leading to the long cycle life, including the effectiveness of the NaBr protective layer on the anode, a tetraglyme/EMIM‐BF₄based electrolyte that prevents oxidation of the VP cathode catalyst surface, and the EMIM‐BF₄ionic liquid aiding in avoiding electrolyte decomposition on NaO₂. 

Thermoelectric (TE) waste heat recovery has attracted significant attention over the past decades, owing to its direct heat-to-electricity conversion capability and reliable operation. However, methods for application-specific, system-level TE design have not been thoroughly investigated. This work provides detailed design optimization strategies and exergy analysis for TE waste heat recovery systems. To this end, we propose the use of TE system equipped on the exhaust of a gas turbine power plant for exhaust waste heat recovery and use it as a case study. A numerical tool has been developed to solve the coupled charge and heat current equations with temperature-dependent material properties and convective heat transfer at the interfaces with the exhaust gases at the hot side and with the ambient air at the heat sink side. Our calculations show that at the optimum design with 50% fill factor and 6 mm leg thickness made of state-of-the-art Bi2Te3 alloys, the proposed system can reach power output of 10.5 kW for the TE system attached on a 2 m-long, 0.5 × 0.5 m2-area exhaust duct with system efficiency of 5% and material cost per power of 0.23 $/W. Our extensive exergy analysis reveals that only 1% of the exergy content of the exhaust gas is exploited in this heat recovery process and the exergy efficiency of the TE system can reach 8% with improvement potential of 85%. 

Abstract: Educator preparation programs have moved away from oering interest-based courses that prepare a teacher candidate on a more surface level and have opted to integrate more authentic experiences with technology that are infused into coursework. This research study focused on redesigning key courses in both the general and special education graduate-level educator preparation programs (EPPs) to infuse learning experiences through a simulated learning environment (Mursion) to help bridge teacher candidates’ coursework and field experiences, oering them robust experience with high leverage practices and technology that increases their own competency. Data from this study demonstrated that preservice teacher candidate work within the Mursion simulated learning environment increased use of high leverage practices related to strategic teaching, collaboration, differentiation, and providing feedback. Implications for instructional coaching, microteaching, repeated practice, and closing the research to practice gap are discussed.