Hydrothermal synthesis of microalgae-derived microporous carbons for electrochemical capacitors
N-doped highly microporous carbons have been successfully fabricated from N-rich microalgae by the combination of low-cost hydrothermal carbonization and industry-adopted KOH activation processes. The hydrothermal carbonization process was found to be an essential step for the successful conversion...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2014 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:dnet:digitalcsic_::dfe6d5908e731b0391aba8af6d03790b |
| Acceso en línea: | http://hdl.handle.net/10261/113963 |
| Access Level: | acceso abierto |
| Palabra clave: | Carbon Energy storage Porosity Biomass Hydrothermal carbonization |
| Sumario: | N-doped highly microporous carbons have been successfully fabricated from N-rich microalgae by the combination of low-cost hydrothermal carbonization and industry-adopted KOH activation processes. The hydrothermal carbonization process was found to be an essential step for the successful conversion of microalgae into a carbon material. The materials thus synthesized showed BET surface areas in the range ∼1800–2200 m2 g−1 exclusively ascribed to micropores. The carbons showed N contents in the 0.7–2.7 wt.%, owing to the use of N-rich microalgae as a carbon precursor. When tested in symmetric double layer capacitors (occasionally called supercapacitors) based on aqueous LiCl electrolytes, pseudocapacitance was only observable for the sample synthesized at the lowest temperature, 650 °C, which is the one exhibiting the largest amount of N- and O-containing groups. The samples synthesized at 700–750 °C exhibited excellent rate capability (only 20% of capacitance loose at 20 A g−1), with specific capacitances of 170–200 F g−1 at 0.1 A g−1. These materials showed excellent long-term cycling stability under high current densities. |
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