Simultaneous improvements in conversion and properties of molecularly controlled CNT fibres

Fibres of ultralong and aligned carbon nanotubes (CNT) have axial properties above reference engineering materials, proving to be exceptional materials for application in structural composites, energy storage and other devices. For CNT fibres produced by direct spinning from floating catalyst chemic...

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Detalles Bibliográficos
Autores: Mikhalchan, Anastasiia, Vila, María, Arévalo, Luis, Vilatela, Juan José
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Rey Juan Carlos
Repositorio:BURJC-Digital. Repositorio Institucional de la Universidad Rey Juan Carlos
OAI Identifier:oai:burjcdigital.urjc.es:10115/27582
Acceso en línea:https://hdl.handle.net/10115/27582
Access Level:acceso embargado
Palabra clave:Carbon nanotube fibres
Floating catalyst
chemical vapor deposition
Carbon conversion
Tensile properties
Electrical conductivity
Descripción
Sumario:Fibres of ultralong and aligned carbon nanotubes (CNT) have axial properties above reference engineering materials, proving to be exceptional materials for application in structural composites, energy storage and other devices. For CNT fibres produced by direct spinning from floating catalyst chemical vapor deposition (FCCVD), a scaled-up method, the challenge is to simultaneously achieve high process conversion and high-performance properties. This work presents a parametric study of the CNT fibre spinning process by establishing the relation between synthesis conditions, molecular composition (i.e. CNT type), fibre mechanical and electrical properties, and conversion. It demonstrates tensile properties (strength 2.1 ± 0.13 N/tex, modulus 107 ± 7 N/tex) above some carbon fibres, combined with carbon conversion about 5%, significantly above literature on similar materials. The combined improvement in conversion and properties is obtained by conducing the reaction at high temperature (1300 °C), using toluene as a carbon source, and through adjustment of the promotor to carbon ratio (S/C) to favor formation of few-layer, collapsed CNTs that maximize packing at relatively high conversions. Lower S/C ratios produce low-defect single-wall CNT, but weaker fibres. An increase in electrical conductivity to 3 × 105 S/m is also observed, with the data suggesting a correlation with longitudinal modulus.