Publications by authors named "Tiago C Mendes"

Rechargeable batteries paired with sodium metal anodes are considered to be one of the most promising high-energy and low-cost energy-storage systems. However, the use of highly reactive sodium metal and the formation of sodium dendrites during battery operation have caused safety concerns, especially when highly flammable liquid electrolytes are used. Here we design and develop solvent-free solid polymer electrolytes (SPEs) based on a perfluoropolyether-terminated polyethylene oxide (PEO)-based block copolymer for safe and stable all-solid-state sodium metal batteries.

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Sodium-ion batteries (SIBs) are widely considered as alternative, sustainable, and cost-effective energy storage devices for large-scale energy storage applications. In this work, an easily fabricated sodium vanadium phosphate-carbon composite (NVP@C) cathode material shows a good rate capability, and long cycle life (89% capacity retention after 5000 cycles at a rate of 10C) with an ionic liquid electrolyte for room temperature sodium metal batteries. The electrochemical performance of a full-cell sodium ion battery with NVP@C and hard carbon electrodes was also investigated at room temperature with an ionic liquid electrolyte.

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Protic salts have been recently recognized to be an excellent carbon source to obtain highly ordered N-doped carbon without the need of tedious and time-consuming preparation steps that are usually involved in traditional polymer-based precursors. Herein, we report a direct co-pyrolysis of an easily synthesized protic salt (benzimidazolium triflate) with calcium and sodium citrate at 850 °C to obtain N-doped mesoporous carbons from a single calcination procedure. It was found that sodium citrate plays a role in the final carbon porosity and acts as an in situ activator.

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