Cellulose nanocrystal-derived carbon electrodes for sustainable potassium-ion charge storage systems
We have here produced carbon electrode materials derived from Crystalline NanoCellulose (CNC) for low-cost potassium-ion based energy storage systems through conventional annealing as well as through a fast and energy efficient microwave assisted carbonization process. A two-step 4-minute synthesis...
| Autores: | , , , , , , , , |
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| Formato: | artículo |
| Fecha de publicación: | 2024 |
| País: | España |
| Recursos: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/103511 |
| Acesso em linha: | https://hdl.handle.net/20.500.14352/103511 |
| Access Level: | acceso abierto |
| Palavra-chave: | 546 Energy storage Carbon Crystalline nanocellulose SupercapacitorK-ion batteries Asymmetric capacitor CNC Hybrid capacitor Aqueous Química inorgánica (Química) Física del estado sólido 2210.05 Electroquímica 3322.02 Generación de Energía 2303 Química Inorgánica |
| Resumo: | We have here produced carbon electrode materials derived from Crystalline NanoCellulose (CNC) for low-cost potassium-ion based energy storage systems through conventional annealing as well as through a fast and energy efficient microwave assisted carbonization process. A two-step 4-minute synthesis with ZnCl2 activation in a domestic microwave leads to a micro/mesoporous carbon with high surface area (SBET~1800 m2 g 1). These CNC-derived carbons, if assessed in symmetric supercapacitor C/C cells cycled with 0.5 M K2SO4 aqueous electrolyte, show reversible capacitance values up to 66 F g 1 at current densities of 5 A g 1, retaining 83% of its initial capacitance after 10.000 cycles without any conducting additive. Due to its large electrochemical window of 1.7 V, a competitive energy density for an aqueous system of 20.9 W h kg 1 is achieved. A hybrid aqueous capacitor built with this carbon as negative electrode and coupled with a Prussian White as positive results in cell capacitance values up to 135 F g 1 under a voltage operation window of 1.8 V in 0.5 M K2SO4. On the other hand, non-activated carbons produced through a 2.25 hour thermal annealing at 900 ◦C, present much lower surface area (SBET~450 m2 g 1), most of it due to its high micropore volume. This low external and mesoporous surface area carbon is a competitive anode material for potassium-ion batteries with a reversible capacity of ~200 mA h g 1 cycled at 28 mA g 1 using 3.9 M KFSI in DME electrolyte (favourably most of it below 1 V vs K+/K) in a potassium half-cell with >80% retention in 100 cycles. The present research shows that sustainable CNC derived carbons produced through energy efficient methods are competitive electrode materials in low-cost K based energy storge systems. |
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