English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Macroscopic fibers of carbon nanotubes (CNT) have emerged as an idealarchitecture to exploit the exceptional properties of CNT building blocks inapplications ranging from energy storage to reinforcement in structuralcomposites. Controlled synthesis and scalability are amongst the most pressingchallenges to further materialize the potential of CNT fibers. This workshowsthat under floating catalyst chemical vapor conditions in the direct spinningmethod, used both in research and industry,the ceramic reactor tube plays anunsuspected active role in CNT growth, leading for example to doubling ofreaction yield when mullite (Al4+2xSi2-2xO10-x(x = 0.4)) is used instead ofalumina (Al2O3), but without affecting CNT morphology in terms of number oflayers, purity or degree of graphitization. This behaviour has been confirmedfor different carbon sources andwhen growing either predominantly single-walledor multi-walled CNTs by adjusting promotor concentration. Analysis of largeSi-based impurities occasionally found in CNT fiber fabric samples, attributedto reactor tube fragments that end up trapped inthe porous fibers, indicatethat the role of the reactor tube is in catalyzing the thermal decomposition ofhydrocarbons, which subsequently react with floating Fe catalyst nanoparticlesand produce extrusion of the CNTs and formation of an aerogel. Reactor gasanalysis confirms that extensive thermal decomposition of the carbon sourceoccurs in the absence of Fe catalystparticles, and that the concentration ofdifferent carbon species (e.g. carbon dioxide and ethylene) is sensitive to thereactor tube type. These finding open new avenues for controlled synthesis ofCNT fibers by decoupling precursor decomposition from CNT extrusion at thecatalyst particle.

Carbon nanotube synthesis and spinning as macroscopic fibers assisted by the ceramic reactor tube