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  1. Doron Aurbach (Ed.)
    Rechargeable Li-CO2 batteries have emerged as promising candidates for next generation batteries due to their low cost, high theoretical capacity, and ability to capture the greenhouse gas CO2. However, these batteries still face challenges such as slow reaction kinetic and short cycle performance due to the accumulation of discharge products. To address this issue, it is necessary to design and develop high efficiency electrocatalysts that can improve CO2 reduction reaction. In this study, we report the use of NiMn2O4 electrocatalysts combined with multiwall carbon nanotubes as a cathode material in the Li-CO2 batteries. This combination proved effective in decomposing discharge products and enhancing cycle performance. The battery shows stable discharge–charge cycles for at least 30 cycles with a high limited capacity of 1000 mAh/g at current density of 100 mA/g. Furthermore, the battery with the NiMn2O4@CNT catalyst exhibits a reversible discharge capacity of 2636 mAh/g. To gain a better understanding of the reaction mechanism of Li-CO2 batteries, spectroscopies and microscopies were employed to identify the chemical composition of the discharge products. This work paves a pathway to increase cycle performance in metal-CO2 batteries, which could have significant implications for energy storage and the reduction of greenhouse gas emissions. 
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    Free, publicly-accessible full text available October 1, 2024
  2. Zinc-based batteries are a scalable and safe alternative to Lithium-ion batteries due to the nature of abundance, low cost and easy to process. In this work, we have successfully synthesized porous zinc electrodes (PZEs) via a gel-binder method that can stably charge and discharge for over 700 h at 1 mA cm −2 before showing signs of failure. We compared PZEs synthesized from small (60 nm), intermediate (10 μ m), and large (150 μ m) zinc particles to determine which surface features are best suited to mitigate dendritic growth and to improve electrolyte stability. The zinc deposits on the large PZE shows a stable and flat morphology, which does not form the hexagonal close-packed (HCP) crystal structure that is typically seen on planar zinc anodes. The intermediate PZE has an increased affinity to deposit onto the glass microfiber separator leading to a decrease of active material on the anode that causes instability during galvanostatic cycling. Both planar zinc and small PZE show HCP deposits that are normal to the surface, which result in very poor electrochemical performance. As the particle size increases, the deposits transition from HCP crystals to flat amorphous metal deposits, increasing cyclic stability. 
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  3. null (Ed.)